Process to manufacture an electro-catalyzed ion exchange membrane, stack comprising one or more units of a flat-shaped electro-catalyzed ion exchange membrane with gas diffusion layers, and device comprising one or more flat-shaped or hollow fiber-shaped electro-catalyzed ion exchange membranes

Description:

The present invention pertains to a process to manufacture an electro-catalyzed ion exchange membrane, a stack comprising one or more units of a flat-shaped electro-catalyzed ion exchange membrane with one or two gas diffusion layers, and a device comprising one or more flat-shaped or hollow fiber-shaped electrocatalyzed ion exchange membranes.

Processes to manufacture an electro-catalyzed ion exchange membrane are known.

One of the most frequently used processes to manufacture an electro catalyzed ion exchange membrane is the ink method which is for example described in Energy Environmental Science, 2020, 13, 3633-3645 :

1 ) A solution of a quaternized poly-carbazole ionomer in aqueous n-propanol is prepared to obtain an ionomer solution.

2) Water, ethanol and isopropyl alcohol are mixed to obtain an aqueous (ethanol/isopropyl alcohol)-solution.

3) Electro catalytic particles consisting of PtRu/C are dispersed over the ionomer solution in the aqueous (ethanol/isopropyl alcohol)-solution.

4) The dispersion obtained in 3) is ultrasonically-treated for more than 30 minutes to obtain the ink for the anode.

5) Electro catalytic particles consisting of Pt/C are dispersed over the ionomer solution in the aqueous (ethanol/isopropyl alcohol)-solution. 6) The dispersion obtained in 5) is ultrasonically-treated for more than 30 minutes to obtain the ink for the cathode.

7) The ink for the anode is directly sprayed onto one surface of a quaternized poly-carbazole anion exchange membrane, and the ink for the cathode is directly sprayed onto the other surface of said anion exchange membrane to obtain an inks-coated anion exchange membrane.

8) The inks-coated anion exchange membrane is dried for more than 12 h to remove residual solvent in the ink layers, and to obtain an ionomercontaining electro-catalyzed anion exchange membrane.

The quaternized poly-carbazole anion exchange membrane used in step 7) of the ink method was prepared via a solvent casting method, wherein quaternized polycarbazole was dissolved in N,N-dimethylformamide, cast onto a glass plate and then dried. The electro-catalyzed anion exchange membrane was sandwiched between two gas diffusion layers without hot-pressing.

US 6,749,892 B2 describes a method to manufacture an electro-catalyzed ion exchange membrane by successively or simultaneously sputter-coating a catalyst metal source, e.g., pure platinum and a carbon source, e.g., nano-sized carbon particles, onto a proton exchange membrane, e.g., a Nation 115 membrane. First of all, water is removed from the surface of the proton exchange membrane in a reaction chamber which is evacuated to a vacuum of 10’ ⁶ Pa or less. Then, sputter-coating is performed at a vacuum in the range of 10-1000 Pa.

US 5,761 ,793 describes a process for the production of a composite comprising an electrode material, a catalyst material and a solid-electrolyte membrane for an electrochemical cell, in particular a fuel cell, wherein solid-electrolyte material, i.e. , an ionomer, is brought into pore-deep contact with the electrode material and the catalyst material, by softening the solid-electrolyte material, comprising the steps of: (a) producing a catalytic powder comprising the electrode material, e.g., carbon particles, the catalyst material, e.g. platinum particles, and the solid-electrolyte material, e.g., Nation particles,

(b) producing a catalytic layer on a carrier, e.g., on a gas diffusion layer, from the catalytic powder,

(c) heating the catalytic layer on a surface facing away from the carrier to soften the solid-electrolyte material; and

(d) subsequently applying the catalytic layer on the carrier to the solid-electrolyte membrane, e.g., to a Nation membrane, under pressure while the solid-electrolyte material is still softened in order to form said composite.

In order to obtain as intimate a composite as possible between the solid-electrolyte membrane and the catalytic layer, it is, where required, advantageous when the solid-electrolyte membrane is brought to a defined temperature, for example heated up, on its upper side facing the catalytic layer prior to the catalytic layer being applied. Such a selective tempering of the solid-electrolyte membrane can be of advantage, depending on the temperature of it, in order to prevent the solidelectrolyte material hardening too quickly when coming into contact with the solidelectrolyte material of the solid-electrolyte membrane due to the lower temperature of the membrane and the cooling caused thereby so that no intimate composite results between the solid-electrolyte membrane and the catalytic layer. The heating up of the solid-electrolyte membrane prior to application of the catalytic layer can, preferably, go so far that the solid-electrolyte membrane softens, in the extreme case will even begin to melt on its surface.

EP 1 531 510 A1 describes a method for coating an ion exchange membrane with a catalyst layer for the use in an electrochemical fuel cell, the method comprising the steps A, B and C, wherein in step A the surface of the ion exchange membrane is heated to soften the membrane surface, for example to a temperature between 20° C and 50° C or 30° C and 40° C above the glass transition temperature (T _g ) of the ion exchange membrane or to a temperature between 130° C and 150 °C, if a Nation membrane is used (T _g of Nation is around 100° C), in step B a catalyst composition, preferably a dry catalyst powder, like a metal black, an alloy or a supported metal-based catalyst, for example platinum supported on carbon particles, is deposited onto the ion exchange membrane, preferably by fluidizing the catalyst composition in a fluidized bed reactor and blowing the catalyst composition onto the heated surface of the ion exchange membrane, and in step C the catalyst composition is compacted into the ion exchange membrane, wherein the term “compacting” encompasses both the application of pressure and temperature, for example through heat calendaring, as well as through the application of only pressure.

US 4,654,104 describes a method for forming a solid polymer electrolyte structure comprising

(a) heating a fluorocarbon membrane, while it is in its thermoplastic form, to a temperature at which it softens;

(b) contacting a plurality of electrically conductive, catalytically active particles with at least a portion of one face of the membrane, while said membrane is in a softened state, thereby forming a membrane/particle combination;

(c) subjecting the membrane/particle combination to a pressure sufficient to embed at least a portion of the particles into the membrane;

(d) contacting the membrane/particle combination with an electrically conductive, hydraulically permeable matrix, thereby forming a particulated membrane/matrix combination, then converting the membrane to its ionic form by reacting it with - in the case of -SO2F pedant groups - 25 weight % NaOH; and

(e) subjecting the particulated membrane/matrix combination to a pressure sufficient to embed at least a portion of the matrix into the particulated membrane. US 2018/0309136 A1 describes a method for coating a substrate in a vacuum, for example an electrolyte membrane of a fuel cell with solid particles which have been electrostatically charged by an electron beam which has been introduced into the solid particles, whereby the solid particles have been separated from one another and accelerated in the direction of the substrate. The solid particles may have a catalyst material and/or a solid electrolyte, i.e. , a solid ionomer. The method needs a vacuum, i.e., a pressure of less than 0.3 bar, or a high vacuum, i.e., a pressure within a range from about 10’ ³ mbar to about 10’ ⁷ mbar, or an ultrahigh vacuum, i.e., a pressure lower than about 10’ ⁷ mbar.

EP 0 787 368 B1 describes a process for producing a membrane/electrode composite comprising a membrane comprising a cation exchanger which is soluble in a solvent, where on at least one side of the membrane there are applied finely divided metals which catalyze the formation of water from H2 and O2, wherein the membrane was provided with a porous surface by means of a phaseinversion process. Said process comprises the steps

(a) allowing a solvent to act on a membrane of an organic polymer which is soluble in an aprotic polar solvent, e.g., dimethylformamide or N-methylpyrrolidone, and comprises units of the formulae formula [Ar ¹ X] and [Ar ² Y], where Ar ¹ and Ar ² are identical or different divalent arylene radicals which are at least partially substituted by carboxylic acid groups, phosphonic acid groups, sulfonic acid groups or sulfonate groups, X is oxgen or sulfur and Y is the carbonyl radical, sulfoxide radical, or sulfonyl radical, so that the surface is partly dissolved,

(b) subsequently treating the membrane with partly dissolved surface with a liquid which is miscible with the solvent but is not a solvent for the membrane material, e.g., water, so that a porous surface is produced, then either

(c) treating the membrane with a solution of a reducing agent for H2PtCle,

(d) freeing the surface of adhering reducing agent by rinsing and then

(e) introducing the membrane into a solution of H2PtCle, so that platinum deposits on its surface, or

(c)’ treating the membrane having a porous surface with an aqueous solution of a potassium, rubidium, cesium or ammonium salt and thus at least partly converting the membrane into its potassium, rubidium, cesium or ammonium salt,

(d)’ treating the membrane on at least one side with a solution of H2PtCle and thus depositing a sparingly soluble hexachloroplatinate on the surfaces,

(e)’ rinsing the membrane and

(f)’ allowing a reducing agent for chloroplatinate ions to act on the membrane, so that firmly adhering aggregates of platinum form on the surface of the membrane, or

(c)” treating the membrane on at least one side with a solution of H2PtCle,

(d)” freeing the surface of the membrane of surface-adhering H2PtCle by rinsing and

(e)” allowing a reducing agent for chloroplatinate ions to act on the membrane, so that metallic platinum deposits on at least one side of the membrane.

US 8,309,275 B2 describes a method for manufacturing a membrane electrode assembly (MEA) using an ion conducting membrane, comprising the steps of:

(a) providing an ion-conductive membrane, e.g., a copolymer of tetrafluorethylene and hexafluorpropylene film which has been radiation grafted with acidic monomers, like vinylsulfonic acid or basic monomers, like 4-vinylpyridine, wherein the grafting solution may comprise crosslinking monomers, wherein the ion-conductive membrane is in a pre-swollen state being impregnated with an ionomer, e.g., with a Nation ionomer, and wherein the state of swelling is conveniently varied by exposing the membrane to one or more liquid solvents including water or organic solvents or to atmospheres containing the vapor phase of one or more solvents;

(b) drying the pre-swollen ion-conducting membrane at elevated temperatures in order to remove residual solvent and to transform the ionomer into the form of an insoluble solid;

(c) after the drying step, re-swelling the ion-conductive membrane by immersing the ion-conductive membrane in a non-boiling solvent;

(d) coating of the ion-conducting membrane on both sides with an electrode layer to form a sandwich; and

(e) hot-pressing the sandwich to form an ion conducting bond between the ion conducting membrane and the electrode layers.

In one embodiment, a coating of catalyst may be applied to the membrane prior to MEA assembly by means of spraying, dipping, sputtering or other methods known in the art. This causes a further process step, if an electro-catalyzed ion exchange membrane shall be manufactured.

The problem of the present invention is to simplify the manufacturing of an electrocatalyzed ion exchange membrane.

Said problem is solved by a process to manufacture an electro-catalyzed ion exchange membrane comprising the combined steps a) providing a film comprising at least on and below its 1 ^st and/or 2 ^nd film surface polymer chains possessing an inter-chain adhesion sufficiently low to seed electro catalytic particles which move in a direction towards said film, wherein said polymer chains bear covalently bound ion exchange groups or functional groups which can be converted into ion exchange groups, b) directing against the 1 ^st and/or 2 ^nd film surface provided in step a) an ionomer- free dust comprising electro catalytic particles having a kinetic energy sufficiently high to move between the polymer chains with sufficiently low inter-chain adhesion on and below the 1 ^st and/or 2 ^nd film surface, as provided in step a), so that a film results, wherein said particles are seeded between said polymer chains on and/or below the 1 ^st and/or 2 ^nd film surface, and c) increasing the inter-chain adhesion of the polymer chains at least on and below the 1 ^st and/or 2 ^nd surface of the film resulting from step b), so that an electrocatalyzed ion exchange membrane results, wherein the polymer chains on and below the 1 ^st and/or 2 ^nd surface of the electro-catalyzed ion exchange membrane anchor the electro catalytic particles on and/or below the 1 ^st and/or 2 ^nd surface of the ion exchange membrane, and wherein the conversion of functional groups into ion exchange groups is performed either after step b) and before step c) or after step c), wherein the sufficiently low inter-chain adhesion of polymer chains at least on and below the 1 ^st and/or 2 ^nd film surface, as required in step a), is provided by a) i) heating the polymer chains which have a melting temperature Tm to a temperature Ti > Tm either a) on the 1 ^st and/or 2 ^nd film surface, so that a surface-molten film results which exhibits molten polymer chains on and below the 1 ^st and/or 2 ^nd film surface, or

P) throughout the film, so that a thoroughly-molten film results which exhibits molten polymer chains throughout the film, or a) ii) solubilizing the polymer chains with an organic solvent either a) on the 1 ^st and/or 2 ^nd film surface, so that a surface-solubilized film results which exhibits solubilized polymer chains on and below the 1 ^st and/or 2 ^nd film surface, or

P) throughout the film, so that a thoroughly-solubilized film results which exhibits solubilized polymer chains throughout the film, or a) iii) swelling crosslinked polymer chains which form a polymer network with an organic solvent, wherein the polymer chains extend between crosslinking points of the polymer network either a) on the 1 ^st and/or 2 ^nd film surface, so that a surface-swollen film results which exhibits swollen polymer chains between the crosslinking points of the polymer network on and below the 1 ^st and/or 2 ^nd film surface, or

P) throughout the film, so that a thoroughly-swollen film results which exhibits swollen polymer chains between the crosslinking points of the polymer network throughout the film, or a) iv) dissolving a first polymer comprising first functional groups in an organic solvent to obtain a solution I, dissolving a second polymer comprising second functional groups in an organic solvent to obtain a solution II, wherein the first functional groups of the first polymer and the second functional groups of the second polymer can be converted into ion exchange groups by a crosslinking quaternization reaction with one another, mixing solution I with solution II to obtain a mixture, and shaping the mixture into a film which contains solubilized polymer chains of the first polymer with first functional groups and solubilized polymer chains of the second polymer with second functional groups throughout the film, so that a thoroughly-solubilized film results which comprises solubilized first polymer chains comprising first functional groups and solubilized second polymer chains comprising second functional groups throughout the film, wherein the increase of the inter-chain adhesion, as required in step c), is provided by

- cooling the film resulting from step b) to a temperature T2 < Tm, if step a) i) has been practiced, or

- removing the organic solvent from the film resulting from step b), if one of the steps a) ii), a) iii), or a) iv) have been practiced, and wherein the electro catalytic particles which have been seeded in step b) and anchored in step c) are accessible for electro catalytic reactions, and wherein the electro-catalyzed ion exchange membrane resulting after step c) is selective in a device, wherein said membrane shall be used.

Said process merely needs process steps a), b), c) and the conversion step, if the polymer chains bear functional groups which can be converted into ion exchange groups. And, as will be explained below, said steps are easily to be performed and neither need an ink, let alone an ionomer containing ink, nor a water removal, nor a vacuum, nor a pressing, nor a phase inversion, nor an adhesive. Therefore, said process simplifies the manufacturing of an electro-catalyzed ion exchange membrane also in respect of a reduced number of substances needed.

The omission of pressing not only saves one process step but also prevents the formation of micro cracks in the membrane which may occur during pressing and reduce the selectivity of the membrane.

Within the scope of the process according to the present invention the terms and wordings used therein have the following meanings: The term “film” which is provided in step a) means a thin coherent layer having a 1 ^st and a 2 ^nd surface, and “thin” means a uniform thickness which safeguards that after step c) an electro-catalyzed ion exchange membrane results with a membrane thickness which fulfills the specific requirements of a device, wherein said membrane shall be used, to convert electrical energy into chemical energy or vice versa, as explained in the following:

If, for example, said device is a H2/O2 fuel cell or an H2O electrolyzer, the thickness of the electro-catalyzed ion exchange membrane ranges from a minimum value which is defined by a desired selectivity, i.e. , by a desired H2- and 02-impermeability to a maximum value which is defined by a desired ion conductivity, i.e., by a desired permeability for H ⁺ or OH’.

If, for example, said device is an all-vanadium redox flow battery, the thickness of the electro-catalyzed ion exchange membrane also ranges from a minimum value which is defined by a desired selectivity, i.e., by a desired impermeability for VO ²⁺ , VO ₂ ⁺ , and V ³⁺ to a maximum value which is defined by a desired ion conductivity, i.e., by a desired permeability for HSO4’ and SO4 ² ’.

Said minimum thickness value of the electro-catalyzed ion exchange membrane may be about 5 pm or about 10 pm, if said membrane is used in a device operating with equal pressure on the 1 ^st and 2 ^nd surface and may be correspondingly higher, if the film is used in a device operating with different pressures on the 1 ^st and 2 ^nd surface. Said maximum thickness value of the electrocatalyzed ion exchange membrane may be about 150 pm or about 200 pm, if the film is used in a device operating with a liquid electrolyte, e.g., aqueous KOH, whereby the maximum thickness value may be the higher the higher the concentration of said liquid electrolyte is.

Preferred values of the thickness of the electro-catalyzed ion exchange membrane may range from about 12 pm to about 140 pm, more preferred from about 15 pm to about 100 pm, and most preferred from about 20 pm to about 50 pm. Here and throughout the present invention the term “about” in connection with a value or a value range means ± 10%, if not defined in a different manner.

The thickness of the film, as provided in step a) exceeds the thickness of the electro-catalyzed ion exchange membrane which results after step c) by a factor which is specific for a selected parameter set for performing steps a), b) and c). Therefore, the thickness of the film as provided in step a) is obtained by multiplying the thickness of the electro-catalyzed ion exchange membrane which results after step c) with said factor.

The film provided in step a) may be flat-shaped or hollow fiber-shaped. If the film is flat shaped, its thickness means the perpendicular distance between its 1 ^st surface, i.e., its top surface and its 2 ^nd surface, i.e., its underside. If the film is hollow fiber-shaped, its thickness means the radial distance between its 1 ^st surface, i.e., its shell surface and its 2 ^nd surface, i.e., its lumen surface. So, if the film is hollow fiber-shaped, its thickness means the thickness of the hollow fiber wall.

The film may be unsupported or supported by a porous supporting material. The supporting material may be a nonwoven or a woven material. In the woven material the distances between its warp and weft yams define the pore size of the supporting material. In the nonwoven material an average pore size is defined by the average distance between the filaments or staple fibers, which have been used to manufacture the nonwoven material. Furthermore, the pores in the porous supporting material may be the result of a thermal induced phase separation, wherein pores with an average pore size result. If the film is supported by a porous supporting material, the film may completely fill the pores of the supporting material or the film may penetrate the pores of the porous supporting material on its first and/or second surface with a penetration depth which is smaller than the thickness of the porous supporting material, so that pore regions remain which are not filled with the film. The term “polymer chains” comprised by the film provided in step a) means a multitude of identical or different recurring units which are covalently bound to one another and form a chain. Preferably the polymer chains are organic polymer chains containing essentially carbon atoms in their backbone.

The film provided in step a) of the present invention comprises polymer chains bearing covalently bound ion exchange groups. Each ion exchange group which is covalently bound to said polymer chain consists of a fixed ion, i.e. , that ion which belongs to the atom group which is covalently bound to the polymer chain and an oppositely charged counter ion.

If the fixed ion is negatively charged, the mobile counter ion is positively charged, and the film comprising polymer chains which such ion exchange groups is a cation exchange film. If the fixed ion is for example -SO2-O" and the counter ion is H ⁺ or a metal cation M ⁺ , the film is a cation exchange film comprising polymer chains according to formula (1 ).

(polymer chain)-SO2-O” H ⁺ or M ⁺ (1 )

If the fixed ion is positively charged, the mobile counter ion is negatively charged, and the film comprising polymer chains which such ion exchange groups is an anion exchange film. If the fixed ion is for example an aliphatic nitronium ion, like -N ⁺ RI R ₂ R ₃ , wherein R ¹ , R ² , and R ³ are independently from one another lower alkyl groups such as methyl or ethyl groups, and the mobile counter ion is OH’ or halide hal’, such as Cl, Br or J’ or SO4 ² ’, the film is an anion exchange film comprising polymer chains according to formula (2).

(polymer chain)-N ⁺ R ¹ R ² R ³ OH’ or hal’ or SO4 ² ’ (2).

Furthermore, the fixed nitronium ion may be part of an aromatic ring, so that it forms an aromatic nitronium ion, for example a pyridinium ion, or an imidazolinium ion. Alternatively, the film provided in step a) of the present invention comprises polymer chains which bear covalently bound functional groups which can be converted into ion exchange groups, i.e. , cation exchange groups or anion exchange groups.

Preferred examples for polymer chains which bear covalently bound functional groups convertible into cation exchange groups are (polymer chain)-SO2-CI and (polymer chain)-SO2-F, which are hydrolysable for example with H2O according to the reactions

(polymer chain )-SO2-CI + H2O —> (polymer chain)-SO2-O‘ H ⁺ + H ⁺ + Cl’ and

(polymer chain )-SO2-F + H2O —> (polymer chain)-SO2-O‘ H ⁺ + H ⁺ + F’.

Said conversion reactions are performed after step c) and can be accelerated by addition of an alkali hydroxide, for example KOH.

Preferred examples for polymer chains which bear covalently bound functional groups which can be converted into anion exchange groups are (polymer chain)- pyridine and (polymer chain)-CH2-hal, wherein hal is Cl, Br, or J. Said polymer chains can react with one another by a crosslinking quaternization reaction, as will be explained later, and said crosslinking quaternization reaction is performed after step b) and before step c).

“Inter-chain adhesion” means the adhesion between the polymer chains resulting from the sum of the attractive inter-chain forces l-IV and the repulsive inter-chain force V. Said forces are explained in the following:

I. Van der Waals inter-chain forces exist between all polymer chains and arise from the formation of temporary instantaneous polarities across a polymer chain from the circulation of electrons. An instantaneous polarity in one polymer chain induces an opposite polarity in an adjacent polymer chain resulting in an inter-chain adhesion force between neighboring polymer chains. II. Dipol-dipol inter-chain forces exist between polar polymer chains having a permanent dipol moment due to uneven sharing of electrons, which gives one part of a polymer chain a partial positive charge 5+ and another part of the polymer chain a partial negative charge 5-, so that the polymer chains are permanent dipoles, which attract one another by the attraction between the 5+ part of one polymer chain and the 5- part of a neighboring polymer chain.

III. Hydrogen bonds are especially strong dipol-dipol inter-chain forces, which occur, if a hydrogen atom is covalently bound for example to nitrogen or oxygen.

IV. Inter-chain ionic attraction forces exist between the fixed ions of a polymer chain and counter ions associated with the fixed ions of a neighbored polymer chain.

V. Inter-chain ionic repulsion forces exist between the fixed ions of a polymer chain and the fixed ions of a neighbored polymer chain and between the counter ions associated with the fixed ions of one polymer chain and the counter ions associated with the fixed ions of a neighbored polymer chain.

The film provided in step a) comprises at least on and below its 1 ^st and/or 2 ^nd film surface polymer chains possessing an inter-chain adhesion sufficiently low to seed electro catalytic particles which move in a direction towards said film. So, the polymer chains on and below the film surface form a zone with sufficiently low inter-chain adhesion. Said zone has to be sufficiently thick, so that the electro catalytic particles with a certain size can be seeded in a manner which ensures that said particles remain between said polymer chains after step b), and are anchored by said polymer chains in step c). For this purpose, it is preferred, that said zone exhibits a zone thickness of > 50 % of the size of the electro catalytic particles. More preferred, said zone thickness amounts to > 60 %, or > 70 %, or > 80 %, or > 90 %, and most preferred to > 100 % of the size of the electro catalytic particles. The meaning of the term “size of the electro catalytic particles” depends on their shape and on their mono- or polydispersity. This is because the shape of the electro catalytic particles may be regular, for example spherical, or irregular, and the size of the electro catalytic particles may be equal, i.e., monodispers, or polydispers. In the latter case said particles exhibit a particles size distribution. In the present application the size of the electro catalytic particles is defined with the aid of their diameter, as explained below for different embodiments:

If the electro catalytic particles (ecps) are spherically shaped and exhibit the same size, their size equals their diameter. So, in this embodiment the equation size of the ecps = diameter of the ecps applies.

If the electro catalytic particles are spherically shaped and exhibit a particle size distribution, their size equals the average diameter of said particle size distribution. So, in this embodiment the equation size of the ecps = average diameter of the ecps applies.

If the electro catalytic particles are irregularly shaped and exhibit the same size, their size equals their equivalent diameter, i.e., the diameter of a circle with an area equal to the projected area of said irregular shaped particles. So, in this embodiment the equation size of the ecps = equivalent diameter of the ecps applies.

If the electro catalytic particles are irregularly shaped and exhibit a particle size distribution, their size equals their average equivalent diameter. So, in this embodiment the equation size of the ecps = average equivalent diameter of the ecps applies. The wording “sufficiently low inter-chain adhesion of polymer chains at least on and below its 1 ^st and/or 2 ^nd film surface” and the ranges for the zone thickness presented above include a zone thickness which is equal to the film thickness. In said embodiment the polymer chains exhibit said sufficiently low inter-chain adhesion throughout the film. Such a zone thickness is provided by each of the embodiments a) i) (3), a) ii) (3), a) iii) [3) and a) iv). Said embodiments maintain the integrity of the film, i.e. , its coherence, the integrity of the chemical structure of the polymer chains, the integrity of the chemical structure of the ion exchange groups, and the integrity of the covalent bonds between the ion exchange groups and the polymer chains.

The sufficiently low inter-chain adhesion of polymer chains at least on and below the 1 ^st and/or 2 ^nd film surface, as required in step a), is provided by each of the steps a) i), a) ii), a) iii) and a) iv). The specific experimental conditions which are presented in the following explanations of said steps focus on embodiments, wherein the 1 ^st and the 2 ^nd film surface are provided with said sufficiently low interchain adhesion in a continuous process. This selection is made, because said embodiments are more interesting for an industrial production, and, because the skilled person is able to translate said embodiments into such embodiments, wherein the sufficiently low inter-chain adhesion is provided only on one surface in a batch process.

In step a) i) said sufficiently low inter-chain adhesion is provided by heating the polymer chains which have a melting temperature Tm to a temperature Ti > Tm either a) on the 1 ^st and/or 2 ^nd film surface, so that a surface-molten film results which exhibits molten polymer chains on and below the 1 ^st and/or 2 ^nd film surface, or

P) throughout the film, so that a thoroughly-molten film results which exhibits molten polymer chains throughout the film. It is emphasized that merely softening the film on and below its surface or throughout the film by heating it to its glass transition temperature T _g or somewhat above is not sufficient to lower the inter-chain adhesion to the extend required in step a) of the process according to the present invention. Rather, the film has to be heated at least to its melting temperature Tm or above Tm. If the film is heated to a temperature above Tm, of course said temperature has to be below the decomposition temperature of the polymer chains. As already explained, the polymer chains on and below the film surface form a zone with sufficiently low inter-chain adhesion which has to be sufficiently thick, so that the electro catalytic particles can be seeded in a manner which ensures that said particles remain between said polymer chains after step b), and are anchored by said polymer chains in step c). In order to achieve a sufficient thickness of said zone, the film is heated to a temperature Ti > Tm for a certain heating time which is the longer the higher the thickness of said zone shall be.

In embodiment a) i) a) such a heating may be achieved by feeding a film comprising polymer chains bearing covalently bound ion exchange groups, i.e. , an ion exchange membrane, or by feeding a film comprising covalently bound functional groups which can be converted into ion exchange groups, i.e., a precursor of an ion exchange membrane through a slit formed by a pair of bars or plates which have been heated to Ti > Tm, wherein the residence time of the film between said bars or plates is short enough, so that a surface-molten film results which exhibits molten polymer chains on and below the 1 ^st and 2 ^nd film surface.

In embodiment a) i) [3) such a heating may be achieved with the same equipment as in embodiment a) i) a) with the mere difference that the residence time of the film between said bars or plates is so long, so that a thoroughly-molten film results which exhibits molten polymer chains throughout the film. Alternatively, embodiment a) i) [3) can be realized during a process to manufacture an ion exchange membrane or its precursor by a melt extrusion process, wherein the as- extruded melt of polymer chains bearing covalently bound ion exchange groups or functional groups which can be converted into ion exchange groups already provides a thoroughly-molten film which exhibits molten polymer chains throughout the film.

In the embodiments a) i) a) and a) i) [3) the molten polymer chains of the surface- or thoroughly-molten film can move relatively to one another and behave similar to a liquid melt. However, said movability is not sufficient to separate the polymer chains from the surface- or thoroughly-molten film. Therefore, said molten polymer chains still cohere with one another. But their inter-chain adhesion becomes sufficiently low, so that electro catalytic particles which in step b) move towards said surface- or thoroughly-molten film with sufficiently high kinetic energy are enabled merely by their kinetic energy to move between the molten polymer chains on and below the 1 ^st and/or 2 ^nd film surface.

In step a) ii) said sufficiently low inter-chain adhesion is provided by solubilizing the polymer chains with an organic solvent either a) on the 1 ^st and/or 2 ^nd film surface, so that a surface-solubilized film results which exhibits solubilized polymer chains on and below the 1 ^st and/or 2 ^nd film surface, or

P) throughout the film, so that a thoroughly-solubilized film results which exhibits solubilized polymer chains throughout the film.

In order to achieve a sufficient thickness of the surface-solubilized zone, the film is contacted with an organic solvent in liquid or gaseous form for a certain contacting time which is the longer the higher the thickness of said zone shall be.

In embodiment a) ii) a) such a contacting may be achieved by feeding a film comprising polymer chains bearing covalently bound ion exchange groups, i.e. , an ion exchange membrane, or by feeding a film comprising covalently bound functional groups which can be converted into ion exchange groups, i.e., a precursor of an ion exchange membrane through an optionally heated bath containing the liquid organic solvent or through an atmosphere saturated with the gaseous organic solvent, wherein the residence time of the film in said bath or atmosphere is short enough, so that a surface-solubilized film results which exhibits solubilized polymer chains on and below the 1 ^st and/or 2 ^nd film surface.

In embodiment a) ii) [3) such a contacting may be achieved with the same equipment as in embodiment a) ii) a) with the mere difference that the residence time of the film in said bath or atmosphere is so long that a thoroughly-solubilized film results which exhibits solubilized polymer chains throughout the film. Alternatively, embodiment a) ii) [3) can be realized during a process to manufacture an ion exchange membrane or its precursor by a solution extrusion process, wherein the as-extruded wet-film of polymer chains bearing covalently bound ion exchange groups or functional groups which can be converted into ion exchange groups already provides a thoroughly-solubilized film which exhibits solubilized polymer chains throughout the film.

In the embodiments a) ii) a) and a) ii) [3) the solubilized polymer chains of the surface-solubilized or thoroughly-solubilized film are surrounded by the organic solvent. The molecules of said solvent establish around the polymer chains a solvent layer, along which the polymer chains can move relatively to one another and behave similar to a solution. However, said movability is not sufficient to separate the polymer chains from the surface- or thoroughly-solubilized film. Therefore, said solubilized polymer chains still cohere with one another. But their inter-chain adhesion becomes sufficiently low, so that electro catalytic particles, which in step b) move towards said surface-solubilized or thoroughly-solubilized film with sufficiently high kinetic energy are enabled merely by their kinetic energy to move between the solubilized polymer chains on and below the 1 ^st and 2 ^nd film surface.

In step a) iii) said sufficiently low inter-chain adhesion is provided by swelling crosslinked polymer chains which form a polymer network with an organic solvent, wherein the polymer chains extend between crosslinking points of the polymer network either a) on the 1 ^st and/or 2 ^nd film surface, so that a surface-swollen film results which exhibits swollen polymer chains between the crosslinking points of the polymer network on and below the 1 ^st and/or 2 ^nd film surface, or

P) throughout the film, so that a thoroughly-swollen film results which exhibits swollen polymer chains between the crosslinking points of the polymer network throughout the film.

In order to achieve a sufficient thickness of the surface-swollen zone, the film is contacted with an organic solvent in liquid form for a certain contacting time which is the longer the higher the thickness of said zone shall be.

In embodiment a) iii) a) such a contacting may be achieved by feeding a film comprising cross-linked polymer chains bearing covalently bound ion exchange groups, i.e. , a cross-linked ion exchange membrane through an optionally heated bath containing the liquid organic solvent, wherein the residence time of the film in said bath is short enough, so that a surface-swollen film results which exhibits swollen polymer chains on and below the 1 ^st and/or 2 ^nd film surface.

In embodiment a) iii) P) such a contacting may be achieved with the same equipment as in embodiment a) iii) a) with the mere difference that the residence time of the film in said bath is so long that a thoroughly-swollen film results which exhibits swollen polymer chains throughout the film. Alternatively, embodiment a) iii) P) can be realized during a process to manufacture a cross-linked ion exchange membrane, wherein a wet film has been shaped and cross-linked but not yet dried, and wherein said film is thoroughly swollen with an organic solvent and contains cross-linked polymer chains bearing covalently bound ion exchange groups. Such a film already provides a thoroughly-swollen film which exhibits swollen polymer chains throughout the film. In the embodiments a) iii) a) and a) iii) [3) the cross-linked polymer chains of the surface-swollen or thoroughly-swollen film are surrounded by the organic solvent. The molecules of said solvent establish around the cross-linked polymer chains a solvent layer, along which the crosslinked polymer chains can move relatively to one another between the crosslinking points of the polymer network to an extent, which is allowed by the crosslinking points of the polymeric network. Therefore, the inter-chain adhesion between the cross-linked polymer chains becomes sufficiently low, so that electro catalytic particles, which in step b) move towards said surface-swollen or thoroughly-swollen film with sufficiently high kinetic energy are enabled merely by their kinetic energy to move between the cross-linked polymer chains on and below the 1 ^st and/or 2 ^nd film surface.

In embodiment a) iv) said sufficiently low inter-chain adhesion is provided by dissolving a first polymer comprising first functional groups, for example pyridine groups, in an organic solvent to obtain a solution I, dissolving a second polymer comprising second functional groups, for example halo alkylene groups hal- (CH2)n- , wherein n may range from 1 to 6, or from 1 to 3, in an organic solvent to obtain a solution II, wherein the first functional groups of the first polymer and the second functional groups of the second polymer can be converted into ion exchange groups by a crosslinking quaternization reaction with one another according to equation [1]

(polymer chain)-pyridine + hal-(CH2)n-(polymer chain) — (polymer chain)-pyridinium ⁺ -(CH2)n-(polymer chain) hal' [1 ], mixing solution I with solution II to obtain a mixture, and shaping the mixture by extruding it into a film which contains solubilized polymer chains of the first polymer with first functional groups and solubilized polymer chains of the second polymer with second functional groups throughout the film, so that a thoroughly- solubilized film results which exhibits solubilized first polymer chains comprising first functional groups and solubilized second polymer chains comprising second functional groups throughout the film.

In embodiment a) iv) the solubilized polymer chains of the first polymer with first functional groups and the solubilized polymer chains of the second polymer with second functional groups in the thoroughly-solubilized film are surrounded by the organic solvent. The molecules of said solvent establish around said polymer chains a solvent layer, along which the polymer chains can move relatively to one another and behave similar to a solution. However, said movability is not sufficient to separate the polymer chains from the thoroughly-solubilized film. Therefore, said solubilized polymer chains still cohere with one another. But their inter-chain adhesion becomes sufficiently low, so that electro catalytic particles, which in step b) move towards said thoroughly-solubilized film with sufficiently high kinetic energy are enabled merely by their kinetic energy to move between said solubilized polymer chains on and below the 1 ^st and/or 2 ^nd film surface.

In step a) iv) the wording “the first functional groups of the first polymer and the second functional groups of the second polymer can be converted into ion exchange groups by a crosslinking quaternization reaction” means that said crosslinking quaternization reaction is not yet performed. Rather, said reaction is suppressed during steps a) and b), for example by sufficiently cooling the first and second solution and the mixture. And after step b) and before step c) said crosslinking quaternization reaction takes place by sufficiently warming in the still solubilized state of said polymer chains.

An example of polymer chains of the first polymer with first functional groups is (polymer chain)-pyridine. An example of polymer chains of the second polymer with second functional groups is hal-CH2-(polymer chain), which can react with (polymer chain)-pyridine according to equation [1], as shown before. Preferred combinations of (polymer chain)-pyridine and hal-CH2-(polymer chain) are listened in table 1 , wherein halide preferably means chloride, bromide or iodide.

Table 1 : Preferred combinations of (polymer chain)-pyridine and hal-CH2- (polymer chain).

A molar ratio N:Yi of 4-vinyl pyridine to styrene in the (polymer chain)-pyridine of combinations 1 and 2 preferably ranges from about 70:30 to about 30:70, more preferable from about 60:40 to about 40:60 and most preferable from about 55:45 to about 45:55, like about 50:50. A molar ratio V:Y2 of vinyl benzyl halide to styrene in the hal-CH2-(polymer chain) of combination 2 preferably ranges from about 70:30 to about 30:70, more preferable from about 60:40 to about 40:60 and most preferable from about 55:45 to about 45:55, like about 50:50. The content in said copolymers allows to manufacture anion exchange membranes both with a high permselectivity P [%] for anions and with an adequate flexibility, as explained in EP 0 187 936 B1 , US 4,871 ,778, and JP 61-162531. If a higher flexibility is required for the membrane, the styrene in the copolymers listed in table 1 may be partly or completely substituted by a terminal diene, e.g., butadiene, pentadiene or hexadiene.

In combinations 1 and 2 a molar ratio N:X of 4-vinyl pyridine in the (polymer chain)-pyridine to vinyl benzyl halide in the hal-CH2-(polymer chain) may range from about 0.5:1 to about 5:1 , more preferred from about 1 :1 to about 4:1 and most preferred from about 1.5:1 to about 3: 1 , like about 2: 1 .

The crosslinking quaternization reaction of the combinations listed above is described in more detail in in EP 0 187 936 B1 , US 4,871 ,778 and JP 61-162531 . Merely one chemical reaction is needed for said crosslinking quaternization. Anion exchange membranes prepared in this manner exhibit a high ex-situ stability in acidic and alkaline environments:

■ The low specific area resistance [o cm ² ] of an anion exchange membrane prepared by a crosslinking quaternization of a copolymer comprising recurring units of 4-vinyl pyridine and styrene and polyvinyl benzyl chloride in aqueous 2 M FeCh/ 1 N HCI at room temperature remains stable for at least 1000 h, as described in Fig. 7 of Journal of Membrane Science, 36 (1988) 535-540.

■ An anion exchange membrane prepared by a crosslinking quaternization of a copolymer comprising recurring units of 4-vinyl pyridine and styrene and polyvinyl benzyl chloride and stored for 9600 h in aqueous 6 N KOH at room temperature showed a decrease in permselectivity measured at room temperature between aqueous 0.5 N/1.0 N KCI from 81 % to 71 %, i.e. merely a 10 % decrease in permselectivity. Said high alkaline stability can be further increased, if the of 4-vinyl pyridine recurring units contain a methyl, ethyl, isopropyl or tertiary-butyl group in the 2-position of the pyridine nucleus, preferably a methyl group.

The copolymers listed in table 1 preferably are random copolymers.

More preferably, at least the copolymers comprising recurring units of 4-vinyl pyridine and styrene in combinations 1 and 2 of table 1are alternating copolymers.

Most preferably, all copolymers in combinations 1 and 2 of table 1 are alternating copolymers. If any one of said combinations is shaped into a thoroughly- solubilized film and subjected to crosslinking quaternization, an anion exchange membrane results consisting of a polymer network, which exhibits transport channels for anions with a uniform pore size in the Angstrom range, as marked by the dotted circle in Fig. 5 which shows a repeating unit of said network, wherein the halide anion has already been exchanged by a hydroxyl anion, and wherein combination 2 has been used with a ratio of N:Yi = 50:50, a ratio of V:Y2 = 50:50 and a ratio of N:X =1 :1 and with a conversion of the crosslinking quaternization of 100 %.

If such an electro-catalyzed anion exchange membrane is used in an alkaline (H2/O2)-fuel cell, the uniform pore size of said membrane ensures

■ a uniform removal of the 4 OH’ formed by the cathodic electro catalytic particles according to reaction O2 + 2 H2O + 4 e- — 4 OH’ from the whole cathodic surface of the electro-catalyzed anion exchange, and

■ a uniform supply of the anodic electro catalytic particles over the whole anodic surface with said 4 OH’, so that the anodic electro catalytic particles are enabled to convert said 4 OH’ together with 2 H2 into H2O in a uniform manner according to reaction 4 OH’ + 2 H2 — ► 4 H2O + 4 e- over the whole anodic surface.

If such an electro-catalyzed anion exchange membrane is used in a H2O- electrolyzer, the uniform pore size of said membrane ensures

■ a uniform removal of the 4 OH’ formed by the cathodic electro catalytic particles according to reaction 4 H2O + 4 e’ — ► 2 H2 + 4 OH’ from the whole cathodic surface, and

■ a uniform supply of the anodic electro catalytic particles over the whole anodic surface with said 4 OH’, so that the anodic electro catalytic particles are enabled to convert said 4 OH’ into O2 and H2O according to reaction

4 OH’ -^ 02 + 2 H2O + 4 e’ over the whole anodic surface.

If such an electro-catalyzed anion exchange membrane is used in a redox flow battery, the uniform pore size of said membrane ensures

■ a uniform removal of the surplus anions (for example Cl’ in an Fe/Cr-redox flow battery or SO4 ² ’ and HSO4’ in an all vanadium redox flow battery) formed by the electro catalytic particles on one surface of the electro- catalyzed membrane through the membrane to the other surface of the electro-catalyzed membrane, where the electro catalytic particles formed an anion deficit.

The uniform pore size of such an anion exchange membrane is in the Angstrom range, and, therefore, generates a very great multitude of transport channels for anions, i.e. , a very low specific area resistance [o cm ² ] of said anion exchange membrane, which in turn reduces the membrane-caused ohmic loss of an electrolyzer or a fuel cells or a redox flow battery containing such an anion exchange membrane. And the very great multitude of transport channels for anions distributes the points, where the catalyzed reactions occur, very uniformly over the whole 1 ^st and 2 ^nd surfaces of the electro-catalyzed anion exchange membrane, if the electro catalytic particles are also uniformly distributed over the whole 1 ^st and 2 ^nd surfaces of the electro-catalyzed anion exchange membrane. This reduces the occurrence of hot spots and increases the working life of the electro-catalyzed ion anion exchange membrane and of a device comprising said membrane.

Correspondingly the same advantages can be achieved, if merely the copolymer comprising recurring units of 4-vinyl pyridine units and styrene units is an alternating copolymer and if said copolymer is subjected to crosslinking quaternization with a polyvinyl benzyl halide. A process to synthesize such an alternating copolymer of 4-vinyl pyridine units and styrene units is described in Polymer Chemistry, 2013, 4, 3575-3581.

If the copolymers listed in the above table are random copolymers, the advantageous effects described above are proportional to the frequency of occurrence of alternating sequences of the respective copolymerized recurring units. If during the traditional production of an ion exchange membrane a film is generated, wherein the polymer chains already possess an inter-chain adhesion according to one of the providing embodiments a) i) (3), a) ii) (3), a) iii) (3), or a) iv), the film in each of said embodiments can directly enter into seeding step b) of the process according to the present invention, whereby thereafter the production of the ion exchange membrane can be finalized as traditionally practiced, i.e. , by the traditional methods to solidify the film. So, if during a traditional production of an ion exchange membrane a film occurs with an inter-chain adhesion as required in one of the providing embodiments a) i) (3), a) ii) (3), a) iii) (3), or a) iv) of the process according to the present invention, the production of the electro-catalyzed ion exchange membrane according to the present invention can be integrated into said traditional process. Said integration saves both

■ those process steps, which otherwise would be necessary to finalize the production of the ion exchange membrane in the traditional manner and

■ those process steps necessary to transform said ready-made ion exchange membrane into a film with an inter-chain adhesion as required in one of the providing embodiments a) i) (3), a) ii) (3), a) iii) (3), or a) iv) of the process according to the present invention.

So, the process according to the present invention may enable a producer of an ion exchange membrane to manufacture an electro-catalyzed ion exchange membrane simply by practicing his established manufacturing till a film according to one of the providing embodiments a) i) (3) , a) ii) (3), a) iii) (3), or a) iv) is generated and then practicing steps b) and c) of the process according to the present invention, whereby step c) can be realized by cooling or drying, i.e., by procedures which the manufacturer practices anyway, if he produces his ion exchange membrane in his traditional manner. In short, the process according to the present invention may enable a manufacturer of an ion exchange membrane to manufacture an electro-catalyzed ion exchange membrane as ever with the mere difference that he adds step b) of the process according to the present invention into his traditional process to manufacture an ion exchange membrane, as will be explained below in more detail.

If in a traditional process to manufacture an ion exchange membrane said membrane is manufactured by melt-extrusion, an intermediate as-extruded film state occurs which already represents a thoroughly-molten film, as required in step a) i) P) of the inventive process. In this case, it is neither necessary to cool said thoroughly-molten film which would have been done, if only an ion exchange membrane would have been manufactured in the traditional manner, nor to re-heat the cooled film to a temperature Ti > Tm. Rather, said as-extruded and, therefore, already thoroughly-molten film can immediately enter directing step b) of the process according to the present invention.

If in a traditional process to manufacture an ion exchange membrane said membrane is manufactured by solvent-casting, an intermediate as-solvent-casted film state occurs which already represents a thoroughly-solubilized film, as required during step a) ii) P) of the inventive process. In this case, it is neither necessary to dry said thoroughly-solubilized film which would have been done, if only an ion exchange membrane would have been manufactured in the traditional manner, nor to re-solubilize said dry film. Rather, said as-solvent-casted and, therefore already thoroughly-solubilized film can immediately enter directing step b) of the process according to the present invention. Analogously the same applies, if in a traditional process to manufacture an ion exchange membrane said membrane is manufactured by extruding a solvent-wet film, wherein the as- solvent-extruded film already represents a thoroughly-solubilized film, as required during step a) ii) P) of the inventive process.

If in a traditional process to manufacture an ion exchange membrane said membrane is manufactured by crosslinking polymer chains in an organic solvent, an intermediate film state occurs, which already represents a thoroughly-swollen film, as required in step a) iii) P) of the inventive process. In this case, it is neither necessary to dry said thoroughly-swollen film which would have been done, if only a crosslinked ion exchange membrane would have been manufactured in the traditional manner, nor to re-swell said film. Rather, said already thoroughly- swollen film can immediately enter directing step b) of the inventive process.

If in a traditional process to manufacture an ion exchange membrane an intermediate state occurs, wherein a film contains a mixture comprising solubilized polymer chains of a first polymer with first functional groups and solubilized polymer chains of a second polymer with second functional groups throughout the film, wherein the first functional groups of the first polymer and the second functional groups of the second polymer are not yet converted into ion exchange groups by a crosslinking quaternization reaction with one another, such a film already represents a thoroughly-solubilized film, as required in step a) iv) of the process according to the present invention. Said already thoroughly-solubilized film can immediately enter directing step b) of the process according to the present invention.

Preferably, an organic solvent used in embodiments a) ii), a) iii), and a) iv) is a polar and aprotic solvent, like N,N’-dimethylformamide (DMF) or N- methylpyrrolidone (NMP), and the wording “an organic solvent” means one of such organic solvents or a mixture of two of such organic solvents, like a mixture of DMF and NMP.

In step b) of the process according to the present invention an ionomer-free dust comprising electro catalytic particles having a kinetic energy sufficiently high to move between the polymer chains with sufficiently low inter-chain adhesion on and below the 1 ^st and/or 2 ^nd film surface is directed against the 1 ^st and/or 2 ^nd film surface, as provided in step a), so that a film results, wherein said particles are seeded between said polymer chains on and/or below the 1 ^st and/or 2 ^nd film surface. Within the scope of the present invention “ionomer” means dry particles comprising polymer chains bearing covalently bound ion exchange groups. The ionomer-free dust comprises electro catalytic particles which may consist of one or more of the elements of the IVA, VA, VIA, VIIA, VIIIA, IB, 11 B and IVB groups of the Periodic Table. And said elements may belong to the same or to different of the just listed groups of the Periodic Table, like Platinum (Pt), Gold (Au), Silver (Ag), Copper (Cu), Palladium (Pd), Ruthenium (Ru), Rhodium (Rh), Iridium (Ir), Tin (Sn), Iron (Fe), Cobalt (Co), Nickel (Ni), Niobium (Nb), or Molybdenum (Mo). Alternatively, said particles may consist of inorganic compounds, like Ni-Fe-layered double hydroxides or alloys of said elements. Furthermore, said element(s), inorganic compounds, or alloys may be supplied on carrier particles, e.g., on carbon black. As already mentioned, the shape of the electro catalytic particles may be regular, for example spherical, or irregular. The already defined size of the electro catalytic particles preferably ranges from the micrometer range down to the sub-nanometer range, for example from about 1 pm to about 0.5 nm, whereby the particle size is the more preferred the smaller it is, because the catalytically active surface of said particles increases with decreasing particle size.

The catalytically active surface can be further increased, if at least some, most preferably all electro catalytic particles are porous which, e.g., is realized in Raney-Nickel. Porous electro catalytic particles exhibit two advantages: The first advantage is, that an electrochemical reaction occurring in a device, wherein the electro-catalyzed ion exchange membrane shall be used, also occurs inside of the electro catalytic particles, because the increased mobility of the polymer chains with sufficiently low inter-chain adhesion, as provided by embodiment a) i), a) ii), and a) iv) allows them to diffuse into the pores of the electro catalytic particles, and, if said pores are large enough compared to the size of said polymer chains, to coat the walls of such pores in a manner, so that after step c) inside of the electro catalytic particles a multitude of channels results into which educts of an electrochemical reaction can diffuse and out of which products of said electrochemical reaction can diffuse.

The second advantage is, that the stability of the electro-catalyzed ion exchange membrane against leaching of the electro catalytic particles during operation of the device, wherein said membrane is used, is further increased, especially in the combination of porous electro catalytic particles and polymer chains with sufficiently low inter-chain adhesion, as provided by embodiment a) iv), because in such a combination a leaching of the electro catalytic particles would need to break covalent chemical bounds of the polymer network.

If the electro catalytic particles exhibit a particle size distribution, it is preferably as narrow as possible. Most preferably the electro catalytic particles exhibit about the same size, i.e. , about the same diameter or equivalent diameter, because in this embodiment the catalytic activity is rather uniformly distributed along the film on and/or along below its surface and later on of the electro-catalyzed ion exchange membrane resulting after step c), so that, if said membrane is used as anode or cathode in a device to convert electrical energy into chemical energy or vice versa, the occurrence of hot spots is reduced or even prevented. In the most preferred embodiment the electro catalytic particles have the same diameter or equivalent diameter in the sub-nanometer range and are porous.

Depending on the specific requirements for anode and cathode of said device, wherein the electro-catalyzed ion exchange membrane may be used, the kind and the amount of the electro catalytic particles which are directed against the 1 ^st film surface may be identical with or different from the kind and amount of the electro catalytic particles, which are directed against the 2 ^nd film surface.

In any case, the kind and amount of electro catalytic particles comprised by the ionomer-free dust used in step b) of the present invention is selected in a manner which effectuates a desired catalytic effectivity for the oxidation and reduction reactions occurring in the device, wherein the electro-catalyzed ion exchange membrane shall be used.

And, in any case, the source of the electro catalytic particles comprised by the ionomer-free dust to be directed against the 1 ^st and/or 2 ^nd film surface is a dry ionomer-free powder comprising said electro catalytic particles, but not whatever ink. In order to prevent or at least suppress flooding of the anode and/or cathode in said device, said ionomer-free dry powder may additionally comprise dry particles comprising a hydrophobizing polymer, like polytetrafluorethylene, or consisting of such a polymer. Furthermore, the ionomer-free dust may comprise a pore forming agent for reasons explained later.

Therefore, within the scope of the present invention the term “ionomer-free dust comprising electro catalytic particles” means a dust containing dry ionomer-free electro catalytic particles, as described above, which may have been mixed with dry particles of a hydrophobizing polymer and/or with dry particles comprising a pore forming agent, but not with an ionomer.

Directing of the ionomer-free dust against the 1 ^st and/or 2 ^nd film surface provided in step a) may be practiced by every method, which is able to finely disperse said dry ionomer-free powder in the required amount and, thereby, to generate the ionomer-free dust, wherein the electro catalytic particles have a kinetic energy sufficiently high to move between the polymer chains with sufficiently low interchain adhesion on and below the 1 ^st and/or 2 ^nd film surface, as provided in step a), so that a film results, wherein said particles are seeded between said polymer chains on and/or below the 1 ^st and/or 2 ^nd film surface. And said method should be able to distribute the electro catalytic particles uniformly between said polymer chains on and below the 1 ^st and/or 2 ^nd film surface. Said requirements are achieved by methods which will be described and illustrated later in Figs. 2, 4, 8 and 8a) which comprise blowing the ionomer-free dust against the 1 ^st and/or 2 ^nd film surface. Said blowing needs application of a pressure. However, because the particle size of the electro catalytic particles is very small and preferably even in the sub-nanometer range, said required blowing pressure is only slightly above atmospheric pressure and orders of magnitude lower than a pressure necessary for whatever pressing or hot pressing carried out by manual presses, flat plate presses, a pressing of a roller or rollers against a flat plate backup member or a roller, as practiced in EP 1 531 510 A1. The absolute value of the blowing pressure depends, among others, from the weight of the electro catalytic particles and from the flux necessary to provide the electro catalytic particles with a kinetic energy sufficiently high to move between the polymer chains with sufficiently low inter-chain adhesion on and below the 1 ^st and/or 2 ^nd film surface.

In any case, no vacuum is needed in the process according to the present invention to seed electro catalytic particles between said polymer chains.

In step b) of the process according to the present invention a film results, wherein the electro catalytic particles are seeded between the polymer chains on and/or below the 1 ^st and/or 2 ^nd film surface. Said seeding of the electro catalytic particles between the polymer chains may lead to three seeding structures as shown schematically in Figs. 1a), 1b) and 1c) which depict cross-sections of the film f and its 1 ^st or 2 ^nd film surface s.

In the first seeding structure (see Fig. 1a) all electro catalytic particles ecp are seeded on the film surface s between the polymer chains with sufficiently low inter-chain adhesion on and below the surface s of the film f, wherein one part of each electro catalytic particle ecp protrudes the surface s of the film f with a protruding length L _pro , and another part of said electro catalytic particle ecp is surrounded by the polymer chains with sufficiently low inter-chain adhesion on and below the surface s of the film f, and, therefore, intrudes into the surface s of the film f with an intruding length Lin. The performance of a device to convert electrical energy into chemical energy or vice versa comprising an electro-catalyzed ion exchange membrane resulting after step c) will be the higher the larger the interfacial area becomes between the surface of the electro catalytic particles ecp and the polymer chains on and below the surface s of the film f. And the electro catalytic particles ecp are seeded in a manner which ensures that said particles remain between said polymer chains after step b), and are anchored by said polymer chains in step c). In consideration of said requirements, the intruding length Lin expressed in relation to the size of the electro catalytic particles ecp which, as already explained, may be the diameter, or the average diameter, or the equivalent diameter, or the average equivalent diameter of the ecp, preferably is in the range of > 50 %, or > 70 %, or > 90 % of the size of the electro catalytic particles ecp, but in each of said embodiments < 100 % of the size of the electro catalytic particles ecp, so that in each of said embodiments the protruding length Lpro is greater than 0 % of the size of the electro catalytic particle ecp . And to every electro catalytic particle ecp which is seeded on the 1 ^st and/or 2 ^nd film surface it applies, that L _pro and Lin is greater than zero, as illustrated in Fig. 1 d), wherein ecp 1 exhibits Lin = 50% and Lpro = 50 % of the ecp size, ecp 2 exhibits Lin = 70% and L _pro = 30 % of the ecp size, and ecp 3 exhibits Lin = 90% and L _pro = 10 % of the ecp size.

In the second seeding structure (see Fig. 1b) all electro catalytic particles ecp are seeded below the film surface s at a distance d of the electro catalytic particles ecp to the surface s of the film f.

In the third seeding structure (see Fig. 1c) some electro catalytic particles ecp (here 2 particles) are seeded on the surface s of the film f, and another part of said electro catalytic particles ecp (here 1 particle) is seeded below the surface s of the film f.

In any case, i.e. , independent from a certain seeding structure, the electro catalytic particles which have been seeded in step b) and anchored in step c) have to be accessible for electro catalytic reactions occurring in a device to convert electrical energy into chemical energy or vice versa. Said requirement is fulfilled for electro catalytic particles which have been seeded on the 1 ^st and/or 2 ^nd film surface. For electro catalytic particles which have been seeded below the 1 ^st and/or 2 ^nd film surface said requirement is the better fulfilled, the smaller d is. Therefore d preferably amounts to the thickness of only a few layers of polymer chains with sufficiently low inter-chains adhesion, for example to the thickness of four, or three, or two, or one or less than 1 one of such layers. The absolute value of d depends on the spatial structure of the polymer chains with sufficient low interchains adhesion below the surface s of the film f. If d is less than the thickness of one of said layers, the absolute value for d may be in a range of only a few Angstrom, e.g., 3, 2, 1 or even 0 Angstrom, as illustrated in Fig. 1 d), wherein d of ecp 4 is small but > 0 and d of ecp 5 = 0. In short, the electro catalytic particles which are seeded below the 1 ^st and/ or 2 ^nd film surface should be seeded at a distance d to the surface s of the film f which is as small as possible and preferably nearly zero or even zero. Even shorter: The electro catalytic particles which are seeded below the 1 ^st and/or 2 ^nd film surface should be seeded near below the film surface. In Fig. 1) d) for each electro catalytic particle 1 to 5 the minimal thickness of the zone with sufficiently low inter-chain adhesion is horizontally hatched.

In order to increase said accessibility for electro catalytic reactions, especially for such particles which are farer away from the1 ^st and/or 2 ^nd film surface, the ionomer-free dust may comprise a pore forming agent to increase the porosity in the region between the 1 ^st and/or 2 ^nd film surface and the electro catalytic particles. Such a pore forming agent may be NH4HCO3 which starts to decompose already at temperatures > 60 °C into gaseous and pore-forming CO2, ammonia and water. So, the pore formation can be initiated during step a) i) or during step c) by thermally removing the organic solvent. If ammonia remains in the obtained electro catalyzed ion exchange membrane, it may be removed by immersing said membrane in the liquid medium which will be used in the electrochemical device, wherein said membrane shall be used. Alternatively, remaining ammonia may be removed during the starting procedures of said device containing the electrocatalyzed ion exchange membrane.

The electro catalytic particles ecp in Figs. 1 a), b) and c) drawn with solid lines do not contact one another. However, it is preferred, that the electro catalytic particles ecp in the seeding structures shown in Figs. 1 a), b) and c) and the electro catalytic particles ecp in the corresponding anchoring structures resulting after step c) contact one another. Said contacting enables conduction of electrons in directions which run more or less parallel to the surfaces of the electro-catalyzed ion exchange membrane. This kind of electron conduction is especially helpful, if the electro-catalyzed ion exchange membrane is hollow-fiber shaped, as will be explained later. And for hollow-shaped fibers it is especially preferred, if the electro catalytic particles ecp not only contact one another but overlap one another, as shown by the ecp depicted with dotted lines in Figs. 1 a), b) and c). In said embodiment it is preferred, if the overlapping areas of the electro catalytic particles ecp are sufficiently large, so that after swelling of the electro-catalyzed ion exchange membrane in the medium applied in the device, wherein said membrane shall be used, said particles are still in contact with one another.

In step c) of the process according to the present invention the increase of the inter-chain adhesion, as required in step c), is provided by cooling the film resulting from step b) to a temperature T2 < Tm, if step a) i) has been practiced, or removing the organic solvent from the film resulting from step b), if one of the steps a) ii), a) iii), or a) iv) have been practiced. Both said cooling and said removing of the organic solvent decrease the mobility of the polymer chains on and below the 1 ^st and/or 2 ^nd film surface, whereby their inter-chain adhesion is increased. And said increased inter-chain adhesion of the polymer chains on and below the 1 ^st and/or 2 ^nd film surface clamps and thereby anchors the electro catalytic particles between said polymer chains, so that after step c) an electrocatalyzed ion exchange membrane results, wherein the polymer chains on and below the 1 ^st and/or 2 ^nd surface of the electro-catalyzed ion exchange membrane anchor the electro catalytic particles.

The increase of the inter-chain adhesion in step c) can be simply achieved by correspondingly reversing the treatment of the film, which was applied in step a) of the process according to the present invention to generate the sufficiently low inter-chain adhesion required therein: If the film has been heated in step a) to a temperature Ti > Tm, said film may be guided through a cooling zone, wherein a cooling gas, e.g., air or better an inert gas, like nitrogen, is blown against the film and cools the film to a temperature T2 < Tm , preferably to room temperature. The temperature of the cooling gas may be room temperature in the whole cooling zone. Alternatively, the temperature of the cooling gas at the entrance of the cooling zone may be T2 < Tm and thereafter decrease differentially or in steps, so that at the exit of the cooling zone the temperature is room temperature. If the film has been treated in step a) with a solvent or a solvent vapor, said film may be guided through a drying zone, e.g., an oven, wherein a vacuum may accelerate the drying.

The electro-catalyzed ion exchange membrane resulting in step c) of the process according to the present invention may exhibit three anchoring structures of the electro catalytic particles on and/or below the 1 ^st and/or 2 ^nd surface of the ion exchange membrane which resemble the seeding structures of the electro catalytic particles shown in Figs. 1a), 1b) and 1c) with respect to the spatial distribution of the electro catalytic particles ecp on and/or below the 1 ^st and/or 2 ^nd surface of the ion exchange membrane, but differ from said seeding structures in density which - as a consequence of the increased inter-chain adhesion - is higher.

The conversion of functional groups into ion exchange groups after step b) and before step c) of the process according to the present invention can be performed for example by reacting first polymer chains comprising first covalently bound functional groups, like (polymer chain)-pyridine, with second polymer chains comprising second covalently bound functional groups, like hal-CH2-(polymer chain) according to a crosslinking quaternization reaction equation [1], as already explained. Alternatively, the conversion of functional groups into ion exchange groups can be performed after step c). In this case, for example polymer chains bearing covalently bound SO2-CI or SO2-F functional groups are hydrolyzed with H2O or with an aqueous alkali hydroxide solution, like a H2O/KOH solution, as already explained.

The electro catalytic particles which have been seeded in step b) and anchored in step c) are accessible for electro catalytic reactions, as already explained, and the electro-catalyzed ion exchange membrane resulting after step c) is selective in a device, wherein said membrane shall be used. The meaning of “selective” depends on the specific requirement of said device:

If, for example, said device is a H2/O2 fuel cell or an H2O electrolyzer, “selective” means, that the electro-catalyzed ion exchange membrane resulting after step c) is impermeable for H2 and O2, but in an acidic electrolyzer or fuel cell permeable for H ⁺ , and in an alkaline electrolyzer permeable for OH’.

If, for example, said device is an all-vanadium redox flow battery, “selective” means, that the electro-catalyzed ion exchange membrane resulting after step c) is impermeable for VO ²⁺ , VO2 ⁺ , and V ³⁺ , but permeable for HSO4’ and SO4 ² ’ .

Preferably, the ionomer-free dust which is directed in step b) of the process according to the present invention against the 1 ^st and/or 2 ^nd film surface provided in step a) has been obtained by dispersing the electro catalytic particles in an inert gas, for example argon or nitrogen. Preferred methods to disperse the electro catalytic particles in the inert gas comprise

(1 ) filling the electro catalytic particles into a tube containing an inert gas and vigorously stirring the particles in said tube, or (2) mounting a tube filed with electro catalytic particles and an inert gas on a vortex shaker and turbulently shaking the tube, or

(3) filling the electro catalytic particles into a funnel equipped with a vibrating screen and passing the particles through the vibrating screen into a stream of inert gas.

So, the dispersing of the electro catalytic particles can be performed in a simple manner with simple and correspondingly cheap equipment.

The process according to the present invention, i.e. , steps a), b) and c), may be performed in a discontinuous manner. However, the process is preferably performed in a continuous manner, as will be explained in more detail later.

An (inert gas/particle)-ratio can be adjusted in a wide range, and, therefore, allows a fine-dosing of the quantity of electro catalytic particles which are directed against and seeded between the polymer chains on and/or below the 1 ^st and/or 2 ^nd film surface provided in step a). Furthermore, if said directing is practiced by blowing, a wide range of blowing velocities can be realized. The wide range of blowing velocities in combination with the wide range of adjustable (inert gas/particle)- ratios enables an even more fine-dosing of the quantity of electro catalytic particles which are directed against and seeded between the polymer chains on and/or below the 1 ^st and/or 2 ^nd film surface provided in step a).

The film provided in step a) of the process according to the present invention is either flat shaped, so that after step c) a flat-shaped electro-catalyzed ion exchange membrane results or hollow fiber-shaped, so that after step c) a hollow fiber-shaped electro-catalyzed ion exchange membrane results.

Figs. 2, 3, and 4 depict embodiments, wherein the film provided in step a) is flat shaped. Furthermore, said figures depict possibilities to perform steps a), b) and c) in a continuous manner. Fig. 2 schematically shows a cross-section through a device 200, wherein dispersing method (2) is used: From first stocks for inert gases 1, T, like gas cylinders filled with a compressed inert gas, e.g., nitrogen, said gases flow through pressure reduction valves 2, 2’, gas purification devices 3, 3’, three-way valves 48, 48’ and inlet pipes 20, 20’ into glass bottles 19, 19’ which are provided with stoppers 21, 2T and filled with a dry powder of ionomer-free electro catalytic particles 7, 7’. Dotted lines 60, 60’ show the fill levels of the electro catalytic particles 7, 7’ in glass bottles 19, 19’. Said glass bottles are mounted on vortex shakers 14, 14’, which are adjusted to a desired shaking intensity given by a certain value for its rotations per minute (rpm). Gas purification devices 3, 3’, for example filters of appropriate pore size, remove impurities which might reduce the catalytic activity of electro catalytic particles 7, 7’ to provide purified inert gases 4, 4’. The combined action of a reduced gas pressure adjusted with reduction valves 2, 2’ and a shaking intensity adjusted with vortex shakers 14, 14’ disperses the electro catalytic particles 7, 7’ in the purified inert gases 4, 4’ and originates ionomer-free dusts 8, 8’ of ionomer-free electro catalytic particles 7, 7’ upstream dotted lines 60, 60’.

Ionomer-free dusts 8, 8’ are transported by the flow of purified inert gases 4, 4’ through outlet pipes 22, 22’ and via slot dies 9, 9’ into directing zones 23, 23’. In directing zones 23, 23’ ionomer-free dusts 8, 8’ are blown onto film 15, which moves in a direction marked by the arrow and which enters device 200 via inlet opening 17, 17’ and moves through directing zones 23, 23’. Film 15 is a flat film which has been provided according to one of the already described embodiments a) i), a) ii), a) iii) or a) iv).

Therefore, Film 15 is a flat film which

- according to embodiment a) i) a) is a surface-molten film which exhibits molten polymer chains on and below its 1 ^st and 2 ^nd surfaces 15a and 15b or according to embodiment a) i) (3) a thoroughly-molten film which exhibits molten polymer chains throughout the film, or - according to embodiment a) ii) a ) is a surface-solubilized film which exhibits solubilized polymer chains on and below its 1 ^st and 2 ^nd surfaces 15a and 15b or according to embodiment a) ii) [3) a thoroughly-solubilized film which exhibits solubilized polymer chains throughout the film, or

- according to embodiment a) iii) a) is a surface-swollen film which exhibits swollen polymer chains between the crosslinking points of the polymer network on and below its 1 ^st and 2 ^nd surfaces 15a and 15b or

- according to embodiment a) iii) [3) a thoroughly swollen film which exhibits swollen polymer chains between the crosslinking points of the polymer network throughout the film, or

- according to embodiment a) iv) a thoroughly-solubilized film which exhibits a mixture of solubilized first polymer chains comprising first functional groups, like (polymer chain)-pyridine, and second polymer chains comprising second functional groups, like hal-CH2-(polymer chain).

The surface molten state of flat film 15 needed to practice embodiment a) i) a) can be achieved by guiding flat film 15 through a zone (not shown in Fig. 2) which has been heated to a temperature Ti > Tm for a time short enough to melt only the polymer chains on and below the 1 ^st and 2 ^nd surfaces 15a and 15b of flat film 15. The thoroughly molten state of flat film 15 needed to practice embodiment a) i) [3) can be achieved by extruding a melt of the polymer chains through an extruder equipped with a slit dye (not shown in Fig. 2). Directing zones 23, 23’ are hold at a temperature Ti > Tm to ensure that the polymer chains remain in their molten state, so that the required sufficiently low inter-chain adhesion of the polymer chains is maintained during the passage of film 15 through directing zones 23, 23’.

The surface solubilized state of flat film 15 needed to practice embodiment a) ii) a) can be achieved by guiding a dry flat film 15 through a bath (not shown in Fig. 2) containing the organic solvent or through an atmosphere saturated with the vapor of said organic solvent (not shown in Fig. 2) for a time short enough to solubilize only the polymer chains on and near below the 1 ^st and 2 ^nd surfaces 15a and 15b of flat film 15. The bath and the atmosphere may be heated to accelerate the required surface solubilization of flat film 15. The thoroughly solubilized state of flat film 15 needed to practice embodiment a) ii) [3) can be achieved by extruding a solution of the polymer chains in the organic solvent through a slit dye to generate a wet film. In directing zones 23, 23’ an atmosphere saturated with a vapor of said organic solvent is established to ensure that the polymer chains remain in their solubilized state, so that the required low inter-chain adhesion of the polymer chains is maintained during the passage of film 15 through directing zones 23, 23’.

The surface swollen state of flat film 15 needed to practice embodiment a) iii) a) can be achieved by guiding a dry flat film 15 through a bath (not shown in Fig. 2) containing the organic solvent or through an atmosphere saturated with the vapor of said organic solvent (not shown in Fig. 2) for a time short enough to swell the crosslinked polymer chains between the crosslinking points of the polymer network on and below the 1 ^st and 2 ^nd surfaces 15a and 15b of the flat film 15. The bath and the atmosphere may be heated to accelerate the required surface swelling of flat film 15. The thoroughly swollen state of flat film 15 needed to practice embodiment a) iii) P) can be achieved by guiding a dry flat film 15 through a bath (not shown in Fig. 2) containing the organic solvent or through an atmosphere saturated with the vapor of said organic solvent (not shown in Fig. 2) for a time long enough to swell the crosslinked polymer chains between the crosslinking points of the polymer network throughout the flat film 15. In directing zones 23, 23’ an atmosphere saturated with a vapor of said organic solvent is established to ensure that the polymer chains remain in their swollen state, so that the required sufficiently low inter-chain adhesion of the polymer chains is maintained during the passage of film 15 through directing zones 23, 23’.

The thoroughly solubilized state of flat film 15 needed to practice embodiment a) iv) can be achieved by extruding a mixture containing solubilized polymer chains of the first polymer with first functional groups and solubilized polymer chains of the second polymer with second functional groups through a slot dye to generate a wet film. In directing zones 23, 23’ an atmosphere saturated with a vapor of said organic solvent is established to ensure that the first and second polymer chains remain in their solubilized state, so that the required sufficiently low inter-chain adhesion of the polymer chains is maintained during the passage of film 15 through directing zones 23, 23’.

In any case, the inter-chain adhesion of the polymer chains at least on and below the surfaces 15a and 15b of flat film 15 is sufficiently low so that electro catalytic particles 7, 7’ comprised by ionomer-free dusts 8, 8’ move between the polymer chains with sufficiently low inter-chain adhesion on and below the film surfaces 15a and 15b merely by their kinetic energy which has been set by the flow velocity of the inert gas, as originated with pressure reduction valves 2, 2’, and are seeded between said polymer chains on and/or below the film surfaces 15a and 15b. This and further parameters which are explained later leads to one of the already described seeding structures depicted in Fig. 1 a), b) and c).

Thereafter, flat film 25 with seeded electro catalytic particles 7, 7’ leaves directing zones 23, 23’ via outlet opening 18, 18’ and enters a cooling or drying device 24, 24’, wherein flat film 25 is cooled, if embodiment a) i) has been applied, or deliberated from the organic solvent, if one of the embodiments a) ii), a) iii), or a) iv) has been applied, by what the electro catalytic particles 7, 7’ are anchored by the polymer chains on and/or below the 1 ^st and 2 ^nd membrane surfaces 15a and 15b, so that an electro-catalyzed ion exchange membrane 29 results with anchored electro catalytic particles 7, 7’ on and/or below the 1 ^st and second surface of said membrane which exhibits a desired catalytic effectivity.

A sufficient contact time of flat film surfaces 15a and 15b with the ionomer-free dust comprising the electro catalytic particles 7, 7’ has to be realized, so that the amount of seeded electro catalytic particles 7, 7’ on and/or below flat film surfaces 15a and 15b is sufficient to produce a desired catalytically effective load during said contact time. Said contact time may be set by a selected length of contact zones 23, 23’ and/or by a selected velocity, at which film 15 is guided through contact zones 23, 23’.

Electro catalytic particles, which have not been seeded by the polymer chains on and/or below the flat film surfaces 15a and 15b are guided in outlet openings 10, 10’, and - after removal of solvent residues, if necessary (not shown in Fig. 2) - recycled via valves 11, 1T into the ionomer-free dust 8, 8’ comprising a certain quantity of electro catalytic particles 7, 7’ finely dispersed in the inert gas. Alternatively, and not shown in Fig. 2, electro catalytic particles 7, 7’, which have not been seeded by the polymer chains on and/or below the flat film surfaces 15a and 15b are guided into storage containers and may be used again after removal of solvent residues, if necessary.

Furthermore, second stocks for inert gas 12, 12’, like gas cylinders filled with a compressed inert gas, e.g. nitrogen, deliver said inert gas into pressure reduction valves 13, 13’, gas purification devices 26, 26’, for example filters of appropriate pore size which remove impurities which might reduce the catalytic activity of electro catalytic particles 7, 7’. The resulting purified inert gases 27, 27’ can be dosed via valves 28, 28’ into the ionomer-free dusts 8, 8’ comprising electro catalytic particles 7, 7’. So, the purified inert gases 27, 27’ can be used to increase the (inert gas/particle)-ratio in ionomer-free dusts 8, 8’. Thereby the (inert gas/particle)-ratio in dusts 8, 8’ can be tuned in a finer and wider range than without said inert gases 27, 27’.

Slot dies 9, 9’ extend vertically from the drawing plane of Fig. 2 and, therefore, are invisible in said figure. Fig. 3 depicts slot dies 9, 9’ and flat film 15 in a three- dimensional drawing. Flat film 15 is moved in a direction marked by the arrow which marks a top down direction identical with the direction marked by the arrow in Fig. 2 The width of slot dies 9, 9’ w _S d may be the same as the width w of film 15. Fig. 3 shows a preferred embodiment with w _S d < w. If in said preferred embodiment the three-way valves 48, 48’ shown in Fig. 2 are switched in positions, wherein purified inert gases 4, 4’ are blown directly into slot dies 9, 9’ for a certain time ti and simultaneously vortex shakers 14, 14’ are turned off for ti , and, if after ti three-way valves 48, 48’ are switched in positions, wherein purified inert gases 4, 4’ are blown via inlet pipes 20, 20’ into glass bottles 19, 19’ and leave glass bottles 19, 19’ via outlet pipes 22, 22’, and the formed dusts 8, 8’ comprising electro catalytic particles 7, 7’ are streamed into slot dies 9, 9’ for a certain other time t2 and simultaneously vortex shakers 14, 14’ are turned on for t2, a tape results after anchoring step c) containing hatched areas representing ion exchange membranes electro-catalyzed on and/or below of the surfaces 15a and 15b and white areas representing ion exchange membranes without electro catalytic particles. Cutting said tape along the dotted line results in flat pieces, wherein each piece contains a region consisting of an electro-catalyzed ion exchange membrane encircled by catalyst-free ion exchange membrane. This facilitates the sealing of said pieces in a stack, wherein the pieces shall be used and reduces the amount of electro catalytic particles 7, 7’ needed.

Fig. 4 schematically shows a cross-section through a device 400 which is also preferably suitable for practicing steps a), b) and c) of the present invention with a flat-shaped film, whereby steps a), b) and c) are performed in a continuous manner. In Fig. 4 same reference numbers refer to same technical contents as in Fig. 2

Device 400 differs from device 200 of Fig. 2 by using dispersion method (3) which is especially suited for very heavy electro catalytic particles 7, 7’, as for example lr-, Pt, or Au-based ones. Dry powders of electro catalytic particles 7, 7’ are stored in funnels 63, 63’ which are filled with an inert gas, e.g., nitrogen. The fill levels of the electro catalytic particles 7, 7’ are shown by dotted lines 60, 60’. Funnels 63, 63’ are equipped with pressure compensating valves 64, 64’ which are connected to reservoirs of purified inert gas at normal pressure (not shown in Fig. 4). Furthermore, funnels 63, 63’ are equipped with vibrating screens 61 , 6T which can be adjusted to a certain frequency. The electro catalytic particles 7, 7’ fall through vibrating screens 61 , 6T and through drop shafts 65, 65’ into the streams of pressure-reduced and purified inert gases 4, 4’ delivered from inert gas stocks 1, T and form ionomer-free dusts 8, 8’ of electro catalytic particles 7, T containing a certain quantity of finely dispersed electro catalytic particles 7, 7’. Ionomer-free dusts 8, 8’ are blown via slot dies 9, 9’ into directing zones 23, 23’, wherein the electro catalytic particles 7, 7’ are directed against film surfaces 15a and 15b of flat film 15. The further processing is done as described in Fig. 2.

From the above descriptions of Fig. 2 and Fig. 4 it becomes intelligibly, that at least the following parameters can be used to achieve a desired load [mg electro catalytic particles per cm ² of membrane surface] and a desired anchoring structure of the electro catalytic particles 7, 7’ in the resulting electro-catalyzed ion exchange membrane 29:

1 . Flow velocity and pressure of purified inert gases 4, 4’ and 27, 27’;

2. Contact time of the electro catalytic particles 7, 7’ with film surfaces 15a and 15b in directing zones 23, 23’;

3. Absolute value of the sufficiently low inter-chain adhesion of the polymer chains of film 15 on and below its 1 ^st and 2 ^nd surfaces 15a and 15b which influences the mobility of the polymer chains on and below film surfaces 15a and 15b and, therefore, the extent, in which electro catalytic particles 7, 7’ move between polymer chains on and below the film surfaces 15a and 15b;

Generally, high values of 1 -2 and low values of 3 favor a high load and an anchoring structure corresponding to seeding structure shown in Fig. 1 b), whereas low values of 1 -2 and high values of 3 favor a low load and an anchoring structure corresponding to seeding structure shown in Fig. 1 a), and medium values of 1 -2 and medium values of 3 favor a medium load and an anchoring structure corresponding to seeding structure shown in Fig. 1 c). After purified inert gases 4, 4’ and 28, 28’ with electro catalytic particles 7, 7’ finely dispersed therein have reached surfaces 15a and 15b of flat film 15, said gases flow along said surfaces and act as gaseous cushions which apply on film surfaces 15a and 15b equal pressures which act as gaseous carriers for film 15 and protect it against mechanical damage. This is especially advantageous in embodiments, wherein film 15 is unsupported and/or in a thoroughly molten, solubilized, or swollen state.

Also in device 400 the width of slot dies 9, 9’ w _S d may be the same as the width w of film 15, but w _S d < w. is preferred. If in said preferred embodiment vibrating screens 61, 6T are switched off for a certain time ti, and, if after ti vibrating screens 61, 6T are switched on for a certain other time t2, a tape results after anchoring step c) containing hatched areas representing ion exchange membranes electro-catalyzed on and/or below of the surfaces 15a and 15b and white areas representing ion exchange membranes without electro catalytic particles, as shown in Fig 3. Cutting said tape along the dotted line results in flat pieces, wherein each piece contains a region consisting of an electro-catalyzed ion exchange membrane encircled by catalyst-free ion exchange membrane. This facilitates the sealing of said pieces in a stack, wherein the pieces shall be used and reduces the amount of electro catalytic particles 7, T needed.

In a preferred embodiment of the process according to the present invention the film provided in step a) is flat-shaped, the flat-shaped film with electro catalytic particles seeded between the polymer chains with sufficiently low inter-chain adhesion is contacted on one or both of its surfaces with a gas diffusion layer, and thereafter step c) is performed, so that after step c) a unit of an electro catalyzed ion exchange membrane with at least one gas diffusion layer results, wherein surface protrusions of the gas diffusion layer are anchored by the polymer chains on and below the 1 ^st and/or 2 ^nd film surface, as will be explained in the following: The sufficiently low inter-chain adhesion of the film provided in step a) of the process according to the present invention enables surface protrusions of a gas diffusion layer to move between the polymer chains on and below the 1 ^st and/or 2 ^nd film surface to become integrated and in step c) to become anchored by the polymer chains on and below the 1 ^st and/or 2 ^nd film surface. The resulting contact area between the electro-catalyzed ion exchange membrane and the gas diffusion layer is larger than a contact area resulting by merely placing the gas diffusion layer on the electro-catalyzed ion exchange membrane. Said enlarged contact area decreases the contact resistance between the electro-catalyzed ion exchange membrane and the gas diffusion layer and correspondingly increases the efficiency of a device, wherein said unit is used.

A gas diffusion layer is a porous electron-conducting layer often made of carbon paper or carbon cloth, or of a metal mesh or foam. The gas diffusion layer allows for the transport of reactants to the electro-catalyzed ion exchange membrane and evenly disperses reactants over the catalytic sites of the electro-catalyzed ion exchange membrane. Furthermore, the gas diffusion layer serves as conductivity path for the electrons to the external circuit via the bipolar plate and vice versa.

Within the scope of the present invention, the gas diffusion layer may or may not be electro-catalyzed.

Figs. 6 and 7 schematically depict embodiments to manufacture units of an electro-catalyzed ion exchange membrane and two gas diffusion layers in a continuous process. In said embodiments device 200 shown in Fig. 2 or device 400 shown in Fig. 4 are used to perform steps b) and c) of the process according to the present invention, and the gas diffusion layers are made of carbon paper composed of carbon staple fibers. The unification of an ion exchange membrane with seeded electro catalytic particles and with two gas diffusion layers may be performed successively, as shown in Fig. 6 or simultaneously, as shown in Fig. 7. In Fig. 6 film 25 with seeded electro catalytic particles 7, T moves in a direction shown by the arrow, leaves directing zones 23, 23’ via outlet opening 18, 18’ and falls by its own weight with its 1 ^st film surface 25a onto a 1 ^st surface 84b of a 1 ^st carbon paper 84 which serves as gas diffusion layer. Carbon paper 84 is unwound from a roll (not shown in Fig. 6) and is transported in a direction shown by the arrow. Film 25 still exhibits the sufficiently low inter chain adhesion of the polymer chains provided in step a). Said sufficiently low inter chain adhesion enables surface fibers 86 of carbon paper 84 to move between the polymer chains on and below the 1 ^st film surface 25a to become integrated by the polymer chains on and below the 1 ^st film surface 25a, as shown in magnification 6a in Fig. 6) Care has to be taken that at the moment, when film 25 falls onto 1 ^st surface 84b of 1 ^st carbon paper 84, the inter-chain adhesion of the polymer chains in film 25 is not too low to prevent filling of the interstices between the fibers 86 in the whole 1 ^st carbon paper 84, because such a filling would destroy the function of gas diffusion layer 84.

A 2 ^nd carbon paper 88, which is unwound from a roll (not shown in Fig. 6) and moves in a direction marked by the arrow falls by its own weight with its 1 ^st surface 88a onto the 2 ^nd film surface 25b of film 25. Care has to be taken that at the moment, when 2 ^nd carbon paper 88 falls onto 2 ^nd film surface 25b, the inter chain adhesion of the polymer chains in film 25 is not too low to prevent that surface fibers 86’ of carbon paper 88 penetrate film 25 so deep that surface fibers 86’ of 2 ^nd carbon paper 88 contact surface fibers 86 of 1 ^st carbon paper 84, because this would generate a short circuit later on in the device, wherein said unit is used.

Film 25 with seeded electro catalytic particles 7, 7’ and integrated surface fibers 86, 86’ of 1 ^st and 2 ^nd carbon papers 84, 88 moves in cooling or solvent removing device 24, 24’, where said film is cooled to a temperature T2 < Tm, if step a) i) has been practiced, or deliberated from the organic solvent, if one of the steps a) ii), a) iii), or a) iv) have been practiced, so that a unit 95 results consisting of an electrocatalyzed ion exchange membrane and two carbon papers as gas diffusion layers which have been applied successively onto film 25. In Fig. 7 film 25 with seeded electro catalytic particles 7, T and with a film thickness dt moves in a direction shown by the arrow, leaves directing zones 23, 23’ via outlet opening 18, 18’ and is simultaneously contacted on its 1 ^st film surface 25a with a 1 ^st surface 84b of a 1 ^st carbon paper 84 which serves as gas diffusion layer and which is unwound from a roll (not shown in Fig. 7) and with a 1 ^st surface 88a of a 2 ^nd carbon paper 88 which serves as gas diffusion layer and which is unwound from a roll (not show in Fig. 7). 1 ^st carbon paper 84 has a thickness di and 2 ^nd carbon paper 88 has a thickness d2 which preferably equals di. “Contacted” means, that counter-rotating guiding rolls 94, 94’ are arranged at a distance dr < di + dt + d2, guiding roll 94 guides 1 ^st carbon paper 84 against the 1 ^st film surface 25a and simultaneously guiding roll 94’ guides 2 ^nd carbon paper 88 against the 2 ^nd film surface 25b. Film 25 still exhibits the sufficiently low inter chain adhesion of the polymer chains provided in step a). Said sufficiently low inter chain adhesion enables surface fibers 86 of 1 ^st carbon paper 84 to move between the polymer chains on and below the 1 ^st film surface 25a and surface fibers 86’ of 2 ^nd carbon paper 88 to move between the polymer chains on and below the 2 ^nd film surface 25b and thereby to become integrated by the polymer chains on and below the 1 ^st and 2 ^nd film surfaces 25a and 25b, so that a film 25 results with seeded electro catalytic particles 7, 7’ and integrated surface fibers 86, 86’ as shown in magnification 6b of Fig. 6. Care has to be taken that the relation dr < di + df + d2 is realized in a manner which safeguards that surface fibers 86 of 1 ^st carbon paper 84 do not contact surface fibers 86’ of 2 ^nd carbon paper 88, because this would lead to a short circuit in a device, wherein said unit is used.

Film 25 with seeded electro catalytic particles 7, 7’ and integrated surface fibers 86, 86’ of 1 ^st and 2 ^nd carbon papers 84 and 88 moves in cooling or solvent removing device 24, 24’, where said film is cooled to a temperature T2 < Tm, if step a) i) has been practiced, or deliberated from the organic solvent, if one of the steps a) ii), a) iii), or a) iv) have been practiced, so that a unit 96 results consisting of an electro-catalyzed ion exchange membrane and two carbon papers 84 and 88 as gas diffusion layers which have been applied simultaneously onto film 25, and wherein surface fibers of carbon papers 84 and 88 are anchored by polymer chains on and below the 1 ^st and 2 ^nd surface of film 25.

If film 25 in Figs. 6 and 7 comprises polymer chains which bear covalently bound functional groups which can be converted into cation exchange groups, like (polymer chain)-SO2-CI, said conversion is performed after step c), for example by hydrolysis with an aqueous alkali hydroxide solution, as already explained. In this case, after step c) film 25 with anchored electro catalytic particles 7, 7’ and surface integrated fibers 86, 86’ of 1 ^st and 2 ^nd carbon papers 84 and 88 leaves cooling device 24, 24’ and is drawn through a bath (not shown in said figures) filled with said aqueous alkali hydroxide solution. Preferably the solution is heated in said bath to accelerate said hydrolysis. After said hydrolysis and after removing of surplus alkali hydroxide a unit 96 results which consists of an electro-catalyzed ion exchange membrane and two carbon papers 84 and 88 as gas diffusion layers.

If film 25 in Figs. 6 and 7 comprises polymer chains which bear covalently bound functional groups which can be converted into anion exchange groups, like (polymer chain)-pyridine and (polymer chain)-CH2-hal, wherein hal is Cl, Br, or J, said conversion is performed after step b) and before step c) by a crosslinking quaternization reaction, as already explained. Said reaction has to be performed in the solvent wet state and has to be inhibited until film 25 with seeded electro catalytic particles 7, 7’ and integrated surface fibers 86, 86’ has been manufactured. For said purposes, the mixture of solubilized (polymer chain)- pyridine and solubilized (polymer chain)-CH2-hal, the slot dies 9, 9’, film 15 shaped by slot dies 9, 9’, directing zones 23, 23’, electro-catalyzed film 25 after leaving directing zones 23, 23’ through outlet openings 18, 18’, 1 ^st and 2 ^nd carbon papers 84 and 88 and guiding rolls 94, 94’ have to be cooled to a temperature at which said crosslinking quaternization is prevented and have to be encased in a manner which prevents that the organic solvent evaporates. Therefore, cooled film 25 with seeded electro catalytic particles after having been united with cooled 1 ^st and 2 ^nd carbon papers 84 and 88 enters a crosslinking quaternization zone (not shown in said figures) which is preferably heated above room temperature to accelerate the crosslinking quaternization and in any case exhibits an atmosphere saturated with the vapor of the organic solvent. After said crosslinking quaternization the resulting cross-linked electro-catalyzed ion exchange membrane united with 1 ^st and 2 ^nd carbon papers 84 and 88 enters drying zone 24, 24’, wherein step c) is performed by removing and preferably recovering the organic solvent, so that a unit 96 results which consists of an electro-catalyzed ion exchange membrane and two carbon papers 84 and 88 as gas diffusion layers which have been applied simultaneously onto film 25 and wherein surface fibers of carbon papers 84 and 88 are anchored by polymer chains on and below the 1 ^st and 2 ^nd surface of film 25.

A stack comprising one or more units of an electro-catalyzed ion exchange membrane with two gas diffusion layers obtained as described above remarkably reduces the number of arranging steps necessary to manufacture the stack and correspondingly increases the speed of stack production, as explained in the following:

Known stacks comprise a positive end plate |+EP|, gas diffusion layers |GDL|, electro-catalyzed ion exchange membranes| eclEMec|, bipolar plates |BP| and a negative end plate |-EP|. Said stack components are arranged as schematically shown below and form the [stack]

[|+EP||GDL||eclEMec||GDL|{|BP||GDL||eclEMec||GDL|}n||-EP| ] with the repeating sequence {|BP||GDL||eclEMec||GDL|}, wherein the number n of the repeating sequences may range up to several hundreds. Consequently, a large number of arranging steps is necessary to manufacture the [stack] from said single components. To compose one repeating sequence

{| BP | |GDL| |eclEMec| |GDL|} from said single components four arranging steps are necessary: Arranging step 1 : |GDL|

Arranging step 2: |eclEMec| + |GDL| — |eclEMec||GDL|

Arranging step 3: |GDL| + |eclEMec||GDL| — |GDL||eclEMec||GDL|

Arranging step 4: |BP| + |GDL||eclEMec||GDL| | BP ||GDL| |eclEMec| |GDL|

However, if the stack is manufactured with |GDL-eclEMec-GDL| units, as described above, merely two arranging steps are needed to compose one repeating sequence {|BP||GDL-eclEMec-GDL|} :

Arranging step 1 : |GDL-eclEMec-GDL|

Arranging step 2: |BP| + |GDL-eclEMec-GDL| — |BP||GDL-eclEMec-GDL|

So, the number of arranging steps to manufacture the repeating sequence mentioned above is halved and the speed of stack production is correspondingly increased.

As mentioned above, the film provided in step a) of the process according to the present invention may be hollow fiber-shaped, so that after step c) a hollow fibershaped electro-catalyzed ion exchange membrane results. If one film is provided in said process, a hollow fiber-shaped electro-catalyzed ion exchange membrane monofilament results. If two or more films are provided in said process, a hollow fiber-shaped electro-catalyzed ion exchange membrane multifilament results. The process described in the following results in a hollow fiber-shaped and electrocatalyzed ion exchange membrane mono- or multifilament. In said process the film provided in step a) is hollow fiber-shaped, and said process comprises the combined steps a) to c), wherein step a) comprises providing an as-spun hollow fiber-shaped mono- or multifilament, wherein each hollow fiber exhibits a shell surface representing the 1 ^st film surface, a lumen surface representing the 2 ^nd film surface, a hollow fiber wall, and throughout said wall polymer chains possessing an inter-chain adhesion sufficiently low to seed electro catalytic particles which move into a direction towards said shell and lumen surface, step b) comprises directing both against said shell and lumen surface of the asspun hollow fiber-shaped mono- or multifilament provided in step a) an ionomer- free dust comprising electro catalytic particles having a kinetic energy sufficiently high to move between the polymer chains with sufficiently low inter-chain adhesion on and below the shell and lumen surface, whereby the electro catalytic particles are seeded between the polymer chains on and/or below said lumen and shell surface, step c) comprises increasing the inter-chain adhesion of the polymer chains throughout the walls of the hollow fibers of the mono- or multifilament resulting from step b), so that a hollow fiber-shaped and electro-catalyzed ion exchange membrane mono- or multifilament results, wherein the polymer chains on and below the shell and the lumen surface anchor the electro catalytic particles on and/or below said shell and lumen surface.

Fig. 8 depicts an embodiment, wherein steps a), b) and c) of said process are performed in a continuous manner and wherein a hollow fiber-shaped monofilament is provided in step a).

Fig. 8 schematically depicts a cross-section of a spinning and electro-catalyzing nozzle 800, wherein steps a) and b) are performed, and wherein a hollow fibershaped and electro-catalyzed ion exchange membrane monofilament is manufactured. Fig. 8 a) schematically depicts a cross-section of the bottom side of nozzle 800. If a hollow fiber-shaped and electro-catalyzed ion exchange membrane multifilament shall be manufactured, two or more nozzles 800 are combined in a spinneret pack 901, which is depicted in Fig. 9 a). Nozzle 800 comprises a metallic base body 812 into which a plurality of bores have been introduced: A central bore 804, an inlet bore 808 which segues into a ring passage bore 838, an inlet bore 840 which segues into a ring passage bore 841 and an inlet bore 808’ which segues into a ring passage bore 838’ which in turn at its bottom end segues into a directing zone 823’ which is oriented perpendicular with respect to ring passage bore 838’. A porous hollow fiber 850 has been fitted into central bore 804. The porous wall of hollow fiber 850 is marked with horizontal lines in Fig. 8) and with radial lines in Fig. 8 a). The porous hollow fiber 850 sticks with its bottom end centrically in a disc 851 which exhibits a diameter 852 sufficiently large to form a directing zone 823 for electro catalytic particles against the lumen surface 857 of the as-spun hollow fiber 860 and a height 853 large enough to ensure mechanical stability of disc 851.

Providing of hollow fiber 850 with disc 851 may comprise vertically dipping one end of hollow fiber 850 onto the ground of a vessel with an inner diameter equal to diameter 852 + x and filled with a liquid cross-linkable monomer composition with a filling height equal to height 853 + y and thereby filling the lumen and the pores of the dipped end of porous hollow fiber 850 with said monomer composition. Crosslinking of the monomer composition causes shrinkage. Length x is the shrinkage of disc 851 in the direction of the diameter 852. Length y is the shrinkage of disc 851 in the direction of the height 853. Crosslinking the monomer composition and removing hollow fiber 850 provided with disc 851 from the vessel results in a porous hollow fiber 850 which centrically sticks with its bottom end in disc 851 and which exhibits a diameter 852 and a height 853. Furthermore, said crosslinking ensures that the whole disc 851 including the sticking part of hollow fiber 850 is gas-tight. Thereafter, hollow fiber 850 provided with disc 851 is inserted into the bottom end of central bore 804 till the top end of hollow fiber 850 reaches the top end of metallic base body 812. The total length, wherein the porous hollow fiber 850 exhibits open, i.e. , gas-permeable pores, amounts to a length 855 plus a protruding length 854 which protrudes the bottom end of central bore 804. Preferably, said protruding length 854 equals the length of directing zones 823’ and 823, as shown in Fig. 8 On the porous wall of the top end of hollow fiber 850 a small quantity of the monomer composition is applied which was used to manufacture disc 851. Said small quantity of the monomer composition flows between the wall of central bore 804 and the porous wall of the top end of hollow fiber 850 and, after having been polymerized, fixes porous hollow fiber 850 in central bore 804. In order to manufacture a hollow fiber-shaped and electro-catalyzed ion exchange membrane monofilament 896 four mass flows are simultaneously streamed through spinning nozzle 800:

A first mass flow 27 is streamed into the lumen of porous hollow fiber 850 as indicated by the arrow. First mass flow 27 contains a pressure reduced and purified inert gas, for example nitrogen, and is generated by a second stock for inert gas 12, a pressure reduction valve 13, and a gas purification device 26, as already described in Figs. 2 and 4.

A second mass flow 8 is streamed into inlet bore 808. Second mass flow 8 contains an ionomer-free dust comprising electro catalytic particles dispersed in an inert gas, for example nitrogen. Preferably, said dispersion is performed by dispersion method (2), as already described in Fig. 2 or by dispersion method (3), as already described in Fig. 4.

A third mass flow 40 is streamed into inlet bore 840 and ring passage bore 841 and exits ring passage bore 841 in the shape of an as-spun hollow fiber 860. Third mass flow 40 contains a hollow fiber-forming mass which may be a) i) P) a melt comprising molten polymer chains bearing functional groups which can be converted into ion exchange groups, e.g., a (polymer chain )-SO2-CI melt, or a) ii) P) a solution comprising solubilized polymer chains bearing cation or anion exchange groups in an organic solvent, or a) iv) a solution comprising a mixture of solubilized first polymer chains comprising first functional groups and solubilized second polymer chains comprising second functional groups in an organic solvent, wherein the first functional groups of the first polymer and the second functional groups of the second polymer can be converted into ion exchange groups by a crosslinking quaternization reaction with one another, as already explained.

A fourth mass flow 8’ is streamed into bore 808’. Mass flow 8’ comprises an ionomer-free dust comprising electro catalytic particles dispersed in an inert gas, for example nitrogen. Preferably, said dispersion is performed by dispersion method (2), as already described in Fig. 2 or by dispersion method (3), as already described in Fig. 4.

The first mass flow 27 is streamed through the lumen of porous hollow fiber 850 and is blazed down at the end of protruding length 854 onto that surface part of gas-impermeable disc 851 which is surrounded by the porous wall of porous hollow fiber 850, by what the inert gas is forced to move from said surface part perpendicular to the direction of porous hollow fiber 850 in all radial directions through the porous wall of porous hollow fiber 850 into directing zone 823, as shown by the small inner arrows in Fig. 8 a).

The second mass flow 8 is streamed through inlet bore 808, enters ring passage bore 838 and at the end of ring passage bore 838 is blazed down onto a border area ba of gas-impermeable disc 851 with diameter 852. By said blazing down second mass flow 8 is forced to move in all radial directions of the border area ba perpendicular to the direction of ring passage bore 838, as shown by the large inner arrows in Fig. 8 a). Said radial movement is further fortified by the radial movement of the inert gas in first mass flow 27. Consequently, the ionomer-free dust comprising electro catalytic particles in second mass flow 8 is additionally forced by the inert gas of first mass flow 27 to move against the whole lumen surface 857 of as-spun hollow fiber 860 which exits ring passage bore 841. Therefore, the electro catalytic particles comprised by second mass flow 8 move between the polymer chains with sufficiently low inter-chain adhesion on and below the whole lumen surface 857 of as-spun hollow fiber 860 and are seeded between said polymer chains on and/or below the whole lumen surface 857 to form seeding structures on and/or below the whole lumen surface 857, as shown in Fig. 1 a), b) and c), wherein now the film surface f is the lumen surface 857 of as-spun hollow fiber 860.

Fourth mass flow 8’ which comprises the ionomer-free dust comprising electro catalytic particles dispersed in the inert gas is blazed down onto directing zone 823’ which is directed perpendicular to ring passage bore 838’ and perpendicular to the direction of as-spun hollow fiber 860. Therefore, the electro catalytic particles of fourth mass flow 8’ are forced to move in all radial directions of directing zone 823’ perpendicular to the shell surface 856 of the as-spun hollow fiber 860, as shown by the large outer arrows in Fig. 8 a). So, electro catalytic particles comprised by fourth mass flow 8’ are forced to move against the whole shell surface 856 of as-spun hollow fiber 860. Therefore, the electro catalytic particles comprised by fourth mass flow 8’ move between the polymer chains with sufficiently low inter-chain adhesion on and below the whole shell surface 856 of as-spun hollow fiber 860 and are seeded between said polymer chains on and/or below the whole shell surface 856 to form seeding structures on and/or below the whole shell surface 856, as shown in Fig. 1 a), b) and c), wherein now the film surface f is the shell surface 856 of as-spun hollow fiber 860.

The summarized pressure of first and second mass streams 27 and 8 equals the pressure of the forth mass stream 8’. So, the inert gases contained in said mass streams simultaneously flow along shell surface 856 and lumen surface 857 with the same pressure and, thereby, act as gaseous cushions which apply on said surfaces 856 and 857 equal pressures which act as gaseous carriers for the wall 860a of as-spun hollow fiber 860 and, thereby, mechanically stabilize as-spun hollow fiber 860.

Regarding the parameters which favor one of the seeding structures shown in Fig 1 a), b) and c) correspondingly the same applies what was already explained for flat-shaped films. Preferably, the electro catalytic particles ecp in the seeding structures shown in Figs. 1 a), b) and c) and in the corresponding anchoring structures contact and, more preferably overlap one another. Said contacting enables conduction of electrons in directions which run more or less parallel to the surfaces of the electro-catalyzed ion exchange membrane monofilament. And said overlapping enables said conduction of electrons also in the case, when the dry electro-catalyzed hollow fiber is swollen in a liquid used in the device, wherein said hollow fiber shall be used. This kind of contacting and overlapping electron conduction is especially helpful, if the electro-catalyzed ion exchange membrane is hollow-fiber shaped, because in the process to manufacture an hollow fibershaped electro-catalyzed ion exchange membrane mono- or multifilament according to the present invention no gas diffusion layers are present, but, nevertheless, electrons generated or consumed by the oxidation or reduction reactions occurring in the device, wherein said electro-catalyzed hollow-fiber shaped ion exchange membrane mono- or multifilament shall be used, have to flow from the anode to the cathode or vice versa of course also in the swollen state of said hollow fiber.

As already explained for flat-shaped films, also in second mass flow 8 and in fourth mass flow 8’ the concentration of electro catalytic particles contained therein may be diluted by mixing said stream with streams of pressure-reduced and purified inert gases.

In order to perform step c), as-spun hollow fiber 860 with seeded electro catalytic particles moves in cooling or drying device 824, wherein as-spun hollow fiber 860 with seeded electro catalytic particles is cooled to a temperature T2 < Tm, if third mass flow 40 is a melt according to the already explained embodiment a) i) (3), or deliberated from the organic solvent, if third mass flow 40 is a solution according to one of the already explained embodiments a) ii) [3) or a) iv), so that a hollow fibershaped and electro-catalyzed ion exchange membrane monofilament 896 results with anchored electro-catalytic particles ecp on and/or below its whole shell surface 856 and on and/or below its whole lumen surface 857. Membrane 896 exhibits anchoring structures which resemble the seeding structures of the electro catalytic particles shown in Figs. 1a), 1b) and 1c) with respect to the spatial distribution of the electro catalytic particles on and/or below the shell surface 856 and the lumen surface 857, but differ from said seeding structures in density which - as a consequence of the increased inter-chain adhesion caused by said cooling or solvent removing - is higher.

If hollow fiber-forming mass 40 comprises a melt exhibiting molten polymer chains bearing functional groups which can be converted into ion exchange groups according to embodiment a) i) (3), the conversion into a cation exchange membrane is performed after step c) in the same manner as already described for flat-shaped films.

If hollow fiber-forming mass 40 comprises a mixture of solubilized first polymer chains comprising first functional groups and solubilized second polymer chains comprising second functional groups, wherein the first functional groups of the first polymer and the second functional groups of the second polymer can be converted by a crosslinking quaternization reaction in an organic solvent according to embodiment a) iv), the conversion into an anion exchange membrane by said crosslinking quaternization is performed after step b) and before step c) in the same manner, as already described for flat-shaped films. This means, among others, that crosslinking quaternization has to be prevented till step b) has been completed. This can be achieved by at least cooling the mixture of said solubilized first and second polymer chains and the spinning nozzle 800 sufficiently below room temperature. To play save, it may further be necessary to cool both the solution of the first polymer chains and the solution of the second polymer chains sufficiently below room temperature.

In any case, the resulting hollow fiber-shaped electro-catalyzed ion exchange membrane monofilament 896 is characterized by a practical equal density of electro catalytic particles anchored on and/or below its whole lumen and shell surface 857 and 856.

The electro catalytic particles anchored on and/or below shell surface 856 may impede the embedding of the hollow fiber-shaped electro-catalyzed ion exchange membrane 896 in a device to convert electrical energy into chemical energy or vice versa. In order to facilitate said embedding and to reduce the amount of electro catalytic particles needed, analogously the same embodiments may be applied, as already described for flat-shaped electro-catalyzed ion exchange membranes:

If in one embodiment the three-way valve 48’ shown in Fig. 2 is switched in a position, wherein purified inert gas 4’ is streamed directly into inlet bore 808’ for a certain time ti and simultaneously vortex shaker 14’ is turned off for ti , and if after ti three-way valve 48’ is switched in a position, wherein purified inert gas 4’ is blown via inlet pipe 20’ into glass bottle 19’ and leaves glass bottle 19’ via outlet pipe 22’ and the formed dust 8’ comprising electro catalytic particles 7’ is streamed into inlet bore 808’ for a certain other time t2 and simultaneously vortex shaker 14’ is turned on for t2, a hollow fiber-shaped electro-catalyzed ion exchange membrane 896 results after anchoring step c) which contains electrocatalyzed shell areas represented in Fig. 9 a) by hatching and non-electro- catalyzed shell areas represented in Fig. 9 a) by white areas. Cutting hollow fibershaped electro-catalyzed ion exchange membrane 896 along the dotted lines shown in Fig. 9 b) results in hollow fibers each of which consisting of an electrocatalyzed shell surface and two non-electro-catalyzed shell surfaces. The latter are needed for embedding.

If in another embodiment vibrating screen 6T is switched off for a certain time ti , so that purified inert gas 4’ is streamed directly into inlet bore 808’ for a certain time ti, and if after ti vibrating screen 6T is switched on for a certain other time t2, so that dust 8’ comprising electro catalytic particles 7’ is streamed into inlet bore 808’ for a certain other time t2, also a hollow fiber-shaped electro-catalyzed ion exchange membrane 896 results after anchoring step c) which contains electrocatalyzed shell areas represented in Fig. 9 a) by hatching and non-electro- catalyzed shell areas represented in Fig. 9 a) by white areas. After cutting along the dotted lines shown in Fig. 9 b) also hollow fibers result each of which consisting of an electro-catalyzed shell surface and two non-electro-catalyzed shell surfaces. The latter are needed for embedding.

Fig. 9 a) shows a spinneret pack 901 comprising a multitude of spinning and electro-catalyzing nozzles 800 which spin a multifilament of hollow fiber-shaped electro-catalyzed ion exchange membranes 896. Each of said membranes 896 exhibits catalyzed shell areas represented by hatching and non-electro-catalyzed shell areas represented by white areas. In technical applications said multifilament may comprise several hundreds of said membranes 896. For the sake of simplicity, only the first three of membranes 896 are shown containing electrocatalyzed shell areas and non-electro-catalyzed shell areas which have been obtained as described above. The lumen areas of membranes 896 are electrocatalyzed along their whole length. The monofilament embodiment deduces itself by centering the attention merely on the left hollow fiber-shaped electro-catalyzed ion exchange membrane 896.

The hollow fiber-shaped and electro-catalyzed ion exchange membrane multifilament may be processed in a process comprising steps d) to f), wherein step d) comprises spacing the filaments of the multifilament resulting from step c) by a spacing distance d _sp from one another to form a parallel array exhibiting one edge filament, intermediate filaments and the other edge filament, winding one or more electron-conducting fibers or threads once or several times around the edge filament with a winding distance d _w between the edge filament and said fibers or threads, guiding said fibers or threads alternately above and below the intermediate filaments with a guiding distance between said fibers or threads and said filaments which equals dw, and winding said fibers or threads once or several times around the other edge filament with a winding distance d _w between the other edge filament and said fibers or threads, wherein dw safeguards, that in a medium of a device to convert electrical energy into chemical energy or vice versa the electro-catalyzed shell surfaces of the medium-swollen filaments contact said fibers or threads but are not damaged by said fibers or threads, whereupon dw is obtained by the swelling factor of said filaments in said medium, and, wherein d _sp safeguards, that said medium can flow along said electro-catalyzed shell surfaces, so that a loosely connected mat results exhibiting hollow fiber-shaped and electrocatalyzed ion exchange membrane filaments, step e) comprises cutting the loosely connected mat resulting from step d) into pieces and immersing the loosely connected mat pieces in said medium which is applied in said device, whereby the hollow fiber-shaped electro-catalyzed ion exchange membrane filaments swell and thus contact the electron-conducting fibers or threads, so that pieces of a contacted mat result exhibiting hollow fibershaped and electro-catalyzed ion exchange membrane filaments, and step f) comprises spirally winding a piece of a contacted mat resulting from step e), so that a piece of a spirally wound mat with contacted hollow fiber-shaped and electro-catalyzed ion exchange membrane filaments results.

Fig. 9 a) illustrates a multifilament resulting from step c) which forms a parallel array exhibiting one edge filament 896, two of a multitude of intermediate filaments 896 and the other edge filament 896 (not shown in Fig. 9 a)). Fig. 9 b) shows, that the filaments of the multifilament which resulted from step c) are spaced from one another by a spacing distance d _sp . And Fig. 9 b) shows the result of winding two electron-conducting fibers or threads 902 twice around the edge filament 896 with a winding distance dw between the edge filament 896 and said two fibers or threads 902, guiding said two fibers or threads 902 alternately above and below the edge filament 896, the intermediate filaments 896, and the other edge filament 896 (not shown in Fig. 9 b)) with a guiding distance between said two fibers or threads 902 and said intermediate filaments 896 which equals dw and winding said two fibers or threads 902 twice around the other edge filament with a winding distance d _w between the other edge filament and said fibers or threads 902 (not shown in Fig. 9 b)). The number of said fibers or threads 902 depends on the ionic conductivity along the electro-catalyzed shell surfaces of membranes 896. The higher said conductivity is the lower is said number. The electron-conducting fibers or threads 902 may be based on a metal or on an electron-conducting polymer. As shown in Fig. 9 b), the electron-conducting fibers or threads 902 connect membranes 896 in a loose manner, so that a loosely connected mat 903 results exhibiting hollow fiber-shaped and electro-catalyzed ion exchange membrane filaments 896. For the sake of completeness it is mentioned that, if merely a hollow fiber-shaped electro-catalyzed monofilament has been spun, electron-conducting fibers or threads 902 are loosely wound once or several times (twice in the embodiment of Fig. 9 b) around the said monofilament. The further proceeding with the monofilament is analogous to the proceeding shown in Figs. 9 c) and e).

According to step e) the loosely connected mat 903 is cut along the dotted lines shown in Fig. 9 b) into pieces which are immersed in that medium which is applied in the device, wherein said pieces of mat 903 shall be used. Said immersion causes membrane filaments 896 to swell and thus to contact the two electronconducting fiber or threads 902 without destroying membrane filaments 896. So, pieces of a contacted mat 904 result exhibiting contacted electro-catalyzed membrane filaments 897, as shown in Fig. 9 c), wherein contacting parts 902a of the two electron-conducting fibers or threads 902 with edge filament 896 have been drawn thicker for the sake of better recognizability of said contacting. The other edge filament 896 and the intermediate filaments 896 are also contacted with the two electron-conducting fibers or threads 902.

According to step f) a peace of contacted mat 904 is spirally wound around a winding axis z parallel to the longitudinal extensions of membrane filaments 896 and perpendicular to the drawing plane, so that a piece of a spirally-wound mat 906 results, as shown in Fig. 9 d), wherein only one winding turn may be sufficient, as shown in Fig. 9 d). For technical applications a piece of a spirally- wound matt 906 may comprise several hundreds or even thousands of membrane filaments 896. In this case correspondingly more winding turns are needed to form a piece of a spirally-shaped matt 906.

A device 905 for connecting electron-conducting fibers or threads 902 with an external electrical circuit is arranged at the end of the two electron-conducting fibers or threads 902. Device 905 extends in the z-y plane and, therefore, cannot be seen in Fig. 9 d), which depicts spirally-shaped matt 906 in the x-y plane.

Fig. 9 e) schematically depicts device 905 in the z-yplane. Device 905 comprises resilient wings 907 and a lock 908. The resilient wings 907 are jointed with the end of one electron-conducting fiber or thread 902 and, if inserted into lock 908, fasten electron-conducting fiber or thread 902 in lock 908 which may be based on a metal or on an electron-conducting polymer.

Furthermore, the present invention pertains to a device to convert electrical energy into chemical energy or vice versa, wherein the device comprises embodiments 1) to 7), wherein

1) comprises one or more flat-shaped electro-catalyzed ion exchange membranes obtained by the process according to claim 4, first alternative,

2) comprises one or more hollow fiber-shaped electro-catalyzed ion exchange membrane filaments obtained by the process according to claim 4, second alternative,

3) comprises one or more units of an electro-catalyzed ion exchange membrane with at least one gas diffusion layer obtained by the process according to claim 5,

4) comprises a stack comprising one or more units of an electro catalyzed ion exchange membrane with two gas diffusion layers obtained from the process according to claim 5,

5) comprises a hollow fiber-shaped and electro-catalyzed ion exchange membrane mono- or multifilament obtained by the process according to claim 7,

6) comprises a piece of a contacted mat exhibiting hollow fiber-shaped and electro-catalyzed ion exchange membrane filaments obtained by the process according to claim 8 after step e), and

7) comprises a piece of a spirally wound mat with contacted hollow fiber-shaped and electro-catalyzed ion exchange membrane filaments obtained by the process according to claim 8 after step f).

Fig. 10 shows a device according to embodiment 6) with a piece of a contacted mat containing two hollow fiber-shaped electro-catalyzed ion exchange membranes and two electron-conducting fibers or threads and schematically depicts a sectional drawing of a device 100 which contains a piece of a contacted mat 904 containing two contacted electro-catalyzed membranes 897 whereof each exhibits a shell surface 110 and a lumen surface 111 and two electron-conducting fibers or threads 902, 902’ which are shown as dotted lines, where they are in contact with shell surfaces 110 and as solid lines, where they are not in contact with shell surfaces 110. Furthermore, electron-conducting fibers or threads 902, 902’ are wound once or several times around the first and second membrane 897, as already shown for the first membrane 897 in Fig. 9 c). The piece of contacted mat 904 is included in a cylindrical case 101 which may be made from an electronically insulating polymer or a glass. Cylindrical case 101 comprises an inlet terminal 112 for educts to be reacted, i.e. , oxidized or reduced, on shell surfaces 110 of contacted electro-catalyzed membranes 897 and an outlet terminal 113 for the corresponding products from the reaction on shell surfaces 110 and for non-reacted educts. Each end of cylindrical case 101 exhibits a top flange 116 and a bottom flange 116’. Each of said top and bottom flanges exhibits holes for top and bottom screws 105, 105’ and a circumferential groove. In the groove of top flange 116 an O-Ring 122 is positioned and in the groove of bottom flange 116’ an O-Ring 122’ is positioned. The piece of contacted mat 904 is fixed in case 101 by devices 905, 905’ for connecting electron-conducting fibers or threads 902, 902’ with an external electrical circuit, as shown in Fig. 9 e), wherein the left ends of electron- conducting fibers or threads 902, 902’ which serve as collectors for electrons generated or consumed by the electro-catalyzed shell surfaces 110 are locked and thereby electronically connected to an external circuit 106 via gas and liquid tight passage 117. In Fig. 10 external circuit 106 is depicted as an anodic one. Alternatively, external circuit 106 may be a cathodic one. Furthermore, membranes 897 of the piece of contacted mat 904 are fixed in case 101 by insulating top and bottom embeddings 104, 104’ which may be made from an epoxy resin. The lumen surfaces 111 of membranes 897 are electro-catalyzed along their whole lengths, whereas the shell surfaces 110 of membranes 897are electro-catalyzed merely along length 108 which extends between top and bottom embeddings 104, 104’. But the shell surfaces 110 of membranes 897 are not electro-catalyzed along length 109, 109’ which equals the height of top and bottom embeddings 104, 104’. This prevents a short cut by migration of electrons along length 109, 109’ of shells 110 to the wall ends of membranes 897 and via top and bottom electron-conducting discs 103, 103’ into the lumen surfaces 111 of membranes 897. Top and bottom electron-conducting discs 103, 103’ may be made of a metal or of an electron-conducting polymer and are arranged directly on top and bottom flanges 116, 116’ and top and bottom embeddings 104, 104’. Each of electron-conducting discs 103, 103’ exhibits holes for top and bottom screws 105, 105’ and an upper and a lower circumferential groove. Electron-conducting discs 103, 103’ serve as collectors for electrons which are generated or consumed by the electro-catalyzed lumen surfaces 111. Said electrons are electronically connected to an external circuit 107 via passages 120, 120’ which are gas and liquid tight. In Fig. 10 external circuit 107 is depicted as a cathodic one. Alternatively, external circuit 107 may be an anodic one. Furthermore, discs 103, 103’ exhibit holes 118, 118’ with an equal hole diameter 119, 119’ which is somewhat smaller than the lumen diameter of membranes 897. Said holes 118, 118’ extend into the lumina 111 of membranes 897 for a length sufficient to tightly hold the ends of membranes 897 between said hole extensions and embeddings 104, 104’. A bottom cap 102’ is arranged directly on bottom disc 103’ and exhibits an inlet terminal 114 for educts to be reacted, i.e., reduced or oxidized, on lumen surfaces 111 of the piece of contacted electro-catalyzed membranes 897. Furthermore, bottom cap 102’ exhibits a circumferential groove and holes for bottom screws 105’. A top cap 102 is arranged directly on top disc 103 and exhibits an outlet terminal 115 for the corresponding products from the reaction on lumen surfaces 111 and for non-reacted educts. Furthermore, top cap 102 exhibits a circumferential groove and holes for top screws 105. Top screws 105 connect top cap 102 with top disc 103 and top flange 116. O-ring 121 serves for a liquid- and gas-tight connection of top disc 103 with top cap 102. O-ring 122 serves for a liquid- and gas-tight connection of top disc 103 with top flange 116. O-ring 12T serves for a liquid- and gas-tight connection of bottom disc 103’ with bottom cap 102’. O-ring 122’ serves for a liquid- and gas-tight connection of bottom disc 103’ with bottom flange 116’.

Fig. 10 a) depicts a perpendicular view on a top disc 103 with 112 holes 118 with equal diameter 119, a circumferential groove 123 for O-ring 121 and 4 holes 124 for top screws 105. Holes 118 of top disc 103 are arranged in a spiral with 7 turns. Therefore, a device 100 with said top disc 103 and a corresponding bottom disc 103’ contains a piece of a spirally wound hollow fiber mat 906 with 7 turns and with 112 contacted electro-catalyzed membranes 897. Generally, devices 100 with even more of said membranes can be manufactured with discs 103, 103’ having a corresponding number of holes 118, 118’ and a piece of a spirally wound hollow fiber mat 906 containing a corresponding number of contacted electro-catalyzed membranes 897.

A process to manufacture device 100 comprises the steps

1) providing case 101,

2) introducing a piece of contacted mat 904 into case 101,

3) connecting the piece of contacted mat 904 with case 101 by revolving the piece of contacted mat 904 and thereby introducing resilient wings 907 at the ends of electron-conducting fibers or threads 902 into lock 908,

4) arranging O-ring 122 in the groove of top flange 116 and O-ring 122’ in the groove of bottom flange 116’,

5) arranging electron-conducting top disc 103 onto top flange 116 and arranging electron-conducting bottom disc 103’ onto bottom flange 116’, 6) arranging O-ring 121 in the other groove of top disc 103, and 0-ring 12T in the other groove of bottom disc 103’,

7) connecting top cap 102, top disc 103 and top flange 116 by top screws 105 and bottom cap 102’, bottom disc 103’ and bottom flange 116’ by bottom screws 105’,

8) filling a liquid comprising the monomers and optionally curing agents required to form top embedding 104 through inlet terminal 112 up to a filling height equal to length 109 and polymerizing to form the top embedding 104, and

9) filling a liquid comprising the monomers and optionally curing agents required to form bottom embedding 104’ through outlet terminal 113 up to a filling height equal to length 109’ and polymerizing to form the bottom embedding 104’.

Steps 1 ) to 9) are facile and, therefore, automatable. This accelerates the production of device 100. In an analogous manner devices can be manufactured with pieces of contacted mats, wherein each of said pieces contains more than two electro-catalyzed hollow fiber shaped ion exchange membranes, for example 100 or 1000 of such membranes. The larger the number of said membranes is chosen, the more advantageous becomes the use of a piece of a spirally wound mat.

Preferably, the device is an electrolyzer, a fuel cell, a unitized reversible fuel cell which can be used either as a fuel cell or as an electrolyzer, or a redox flow battery.

If the energy to be converted is high, two or more of said devices may be connected in series.

If the energy to be converted is very low and if the device is a fuel cell, it can be used as a sensor to detect traces of a fuel, for example H2, or of an oxidant, for example O2 or CH3CH2OH, in atmospheres, wherein the concentration of said fuel or oxidant shall not exceed certain threshold values.

In the following further special experimental conditions are described to achieve in the embodiments a) i), a) ii), a) iii) and a) iv) on and below the 1 ^st and/or 2 ^nd film surface an inter-chain adhesion of the polymer chains sufficiently low to seed electro catalytic particles which move in a direction towards said film:

If, for example, the polymer used in embodiments a) i) a) or [3) is a perfluorosulfonyl fluoride, like Aquivion® P87S-SO2F from Solvay which is a copolymer of tetrafluorethylene F2C=CF2 with sulfonyl fluoride vinyl ether F2C=CF-O-CF2CF2-SO2-F and which has a melt mass-flow rate measured according to ASTM D1238 at 280°C/5.0 kg of 50 g/10 min, such an Aquivion® P87S-SO2F film contains at 280 °C molten chains of said copolymer either on its 1 ^st and/or 2 ^nd surface or throughout said film which can move relatively to one another and behave similar to a liquid melt. However, said movability is not sufficient to separate said copolymer chains from said surface- or thoroughly- molten Aquivion® P87S-SO2F film. Therefore, said molten copolymer chains still cohere with one another. But their inter-chain adhesion becomes sufficiently low, so that electro catalytic particles which in step b) move towards said surface- or thoroughly-molten film with sufficiently high kinetic energy are enabled merely by their kinetic energy to move between the molten copolymer chains on and below the 1 ^st and/or 2 ^nd surface of said Aquivion® P87S-SO2F film, as provided in step a). Therefore, if in embodiments a) i) a) or [3) such an Aquivion® P87S-SO2F film is used, T1 should amount to 280 °C or even somewhat above 280 °C, because above 280 °C the movability of said copolymer chains is even higher than at 280 °C, so that at T1 > 280 °C it becomes even easier for the electro catalytic particles to move between said molten copolymer chains on and below the 1 ^st and/or 2 ^nd film surface of such an Aquivion® P87S-SO2F film, as provided in step a).

Furthermore, at T1 > 280 °C the ratio of the seeding structures which are illustrated in Figs. 1a), 1b) and 1c) is shifted in favor of the seeding structures shown in Figs. 1b) and 1c), so that the interfacial area between the electro catalytic particles and said polymer chains with sufficiently low inter-chain adhesion is increased. Said increased interfacial area effectuates, that after step c) an electrocatalyzed ion exchange membrane results which provides a device to convert electrical energy into chemical energy or vice versa with an even higher conversion rate.

If, for example, the polymer used in embodiments a) ii) a) or [3) is a poly(carbazole)-based anion conducting material, like QPC-TMA in a 25 wt.% solution in DMF, as described in Energy Environmental Science, 2020, 13, 3633- 3645 which is cited at the start of this description, a film manufactured with a 25 wt.% solution of said polycarbazole in DMF contains either on its 1 ^st and/or 2 ^nd surface or throughout said film solubilized polycarbazole chains which are surrounded by the DMF solvent. The DMF molecules establish around said QPC- TMA polycarbazole chains a solvent layer, along which said polycabazole chains can move relatively to one another and behave similar to a solution. However, said movability is not sufficient to separate said polycarbazole chains from said surface- or thoroughly-solubilized QPC-TMA polycarbazole film. Therefore, said solubilized polymer chains still cohere with one another. But their inter-chain adhesion becomes sufficiently low, so that electro catalytic particles, which in step b) move towards said surface-solubilized or thoroughly-solubilized QPC-TMA polycarbazole film with sufficiently high kinetic energy are enabled merely by their kinetic energy to move between the solubilized polycarbazole chains on and below the 1 ^st and 2 ^nd surface of said QPC-TMA polycarbazole film, as provided in step a). Therefore, if in embodiments a) ii) a) or [3) said QPC-TMA polycarbazole is used to provide a film with sufficiently low inter-chain adhesion on and below its 1 ^st and/or 2 ^nd surface, the concentration of the QPC-TMA polycarbazole in its DMF solution should amount to c = 25 wt.% or even somewhat below 25 wt.%, because below 25 wt.% the movability of said QPC-TMA polycarbazole chains is even higher than at 25 wt.%, so that at c < 25 wt.% it becomes even easier for the electro catalytic particles to move between said solubilized chains on and below the 1 ^st and/or 2 ^nd film surface of such an QPC-TMA polycarbazole film, as provided in step a). Furthermore, at c < 25 wt.% the ratio of the seeding structures which are illustrated in Figs. 1a), 1b) and 1c) is shifted in favor of the seeding structures shown in Figs. 1b) and 1c), so that the interfacial area between the electro catalytic particles and said polymer chains with sufficiently low inter-chain adhesion is increased. Said increased interfacial area effectuates, that after step c) an electrocatalyzed ion exchange membrane results which provides a device to convert electrical energy into chemical energy or vice versa with an even higher conversion rate.

If, for example, the polymer network used in embodiments a) iii) a) or [3) is obtained with divinylbenzene (DVB) as the crosslinking agent, the crosslinked polymer chains which extend between the DVB crosslinking points of said network are swollen with an organic solvent, e.g., with DMF or NMP. The molecules of the organic solvent, e.g., of DMF or NMP, surround the polymer chains of the surface- swollen or thoroughly-swollen film and establish around said DVB-crosslinked polymer chains a solvent layer, along which said polymer chains can move relatively to one another between the DVB-crosslinking points of the polymer network to an extent, which is allowed by the DVB-crosslinking points of the polymeric network. Therefore, the inter-chain adhesion between the DVB- crosslinked polymer chains becomes sufficiently low, so that electro catalytic particles, which in step b) move towards said surface-swollen or thoroughly- swollen film with sufficiently high kinetic energy are enabled merely by their kinetic energy to move between said solubilized and DVB-crosslinked polymer chains on and below the 1 ^st and/or 2 ^nd film surface, as provided in step a). The swelling degree of said polymer network is quantified by the swelling factor f which is defined as f = volume of the swollen network/volume of the dry network and, therefore, is > 1 . The f value is the higher the lower the crosslinking density of the network is which is defined as the number of crosslinking points per unit volume. And the crosslinking density is the lower the lower the DVB amount is which was used to synthesize the network. If said DVB amount was so low, that f becomes 1 .2 or even somewhat above 1 .2, the movability of the polymer chains is higher than at f<1 .2, so that f > 1 .2 it becomes even easier for the electro catalytic particles to move between said swollen and DVB-crosslinked polymer chains on and below the 1 ^st and/or 2 ^nd film surface, as provided in step a). Furthermore, in comparison to f < 1 .2, at f > 1 .2 the ratio of the seeding structures which are illustrated in Figs. 1a), 1b) and 1c) is shifted in favor of the seeding structures shown in Figs. 1b) and 1c), so that the interfacial area between the electro catalytic particles and said polymer chains with sufficiently low inter-chain adhesion is increased. Said increased interfacial area effectuates, that after step c) an electro-catalyzed ion exchange membrane results which provides a device to convert electrical energy into chemical energy or vice versa with an even higher conversion rate.

If, for example, for embodiment a) iv) the combination 1 of table 1 is used, the further special experimental conditions read as follows:

- The copolymer of 4-vinyl pyridine and styrene has a molar ratio N:Yi of 4-vinyl pyridine to styrene of 60:40, exhibits an intrinsic viscosity [r|] of

186 cm ³ /g measured in DMF and is dissolved in DMF to result in a solution I with a concentration of 100 g/l.

- The polyvinyl benzyl chloride exhibits an intrinsic viscosity [r|] of 32 cm ³ /g measured in DMF and is dissolved in DMF to result in a solution II with a concentration of 370 g/l.

- Solution I is mixed with solution II in a volume ratio of 10:1 to obtain a mixture which is shaped into a film.

Said film contains DMF-solubilized chains of the copolymer of 4-vinyl pyridine with styrene and DMF-solubilized chains of the polyvinyl benzyl chloride. The DMF molecules establish around said (co-)polymers a solvent layer, along which said (co-)polymer chains can move relatively to one another and behave similar to a solution. However, said movability is not sufficient to separate said (co-)polymer chains from the thoroughly-solubilized film. Therefore, said solubilized (copolymer chains still cohere with one another. But their inter-chain adhesion becomes sufficiently low, so that electro catalytic particles, which in step b) move towards said thoroughly solubilized film with sufficiently high kinetic energy are enabled merely by their kinetic energy to move between the solubilized (co)- polymer chains.

The intrinsic viscosities mentioned above are measured as described by Wayne R. Sorenson and Tod W. Campbell on page 35 of “Preparative Methods of Polymer Chemistry”, INTERSCIENCE PUBLISHERS, INC., NEW YORK, 1961.

Regarding other polymers or polymer networks with covalently bound ion exchange groups or functional groups which can be converted into ion exchange groups, the special experimental conditions to provide films with said polymers or polymer networks comprising at least on and below their 1 ^st and/or 2 ^nd surfaces polymer chains which possess an inter-chain adhesion sufficiently low to seed electro catalytic particles which move in a direction towards said films, can be simply achieved for all embodiments a) i), a) ii), a) iii) and a) iv), as explained in the following:

Embodiment a) i):

(1 ) Fill the polymer in a test glass.

(2) Heat the polymer to a temperature Ti > Tm.

(3) Dip a glass rod into the melt.

(4) Lift the glass rod out of the melt and observe, whether the down flowing melt forms a thread:

If yes: Ti is the temperature which provides films with the required sufficiently low inter-chain adhesion.

If not: Repeat (1 )-(4) with a somewhat lower temperature than Ti.

If the polymer is already used for melt extrusion, Ti is already known as the temperature of extruding.

Embodiment a) ii):

(1 ) Fill the dry polymer in a test glass. (2) Dissolve the polymer in an organic solvent with a polymer concentration ci.

(3) Dip a glass rod into the solution.

(4) Lift the glass rod out of the solution and observe, whether the down flowing solution forms a thread:

If yes: ci is the concentration which provides films with the required sufficiently low inter-chain adhesion.

If not: Repeat (1 )-(4) with a somewhat higher concentration than ci.

If the polymer is already used for solvent extrusion, ci is already known as the concentration of spin dope for solvent casting or solvent extruding.

Embodiment a) iii):

(1 ) Fill the dry polymer network which has been manufactured with an amount of crosslinking agent aocai in a test glass and mark the filling level.

(2) Swell said network in an organic solvent and mark the filling level of the swollen network.

(3) Determine the swelling ratio fi and use said network with said fi.

If it is desired to further facilitate the movement of the electro catalytic particles between the crosslinked polymer chains, use a polymer network with the same constituents but with a somewhat lower aoca.

If the polymer network is already used to manufacture a crosslinked ion exchange membrane, aocai and f are already known as the concentration and swelling ratio used in manufacturing the crosslinked ion exchange membrane.

Embodiment a) iv):

(1 ) Fill the mixture of solution I with solution II in a test glass.

(2) Dissolve the mixture in an organic solvent with a mixture concentration Cmix.

(3) Dip a glass rod into the mixture.

(4) Lift the glass rod out of the mixture and observe, whether the down flowing mixture forms a thread:

If yes: Cmix is the concentration which provides films with the required sufficiently low inter-chain adhesion.

If not: Repeat (1)-(4) with a somewhat higher concentration than Cmix.

If the polymer mixture is already used to manufacture an ion exchange membrane by crosslinking quaternization, Cmix is already known as the concentration of the components of the crosslinking quaternization process. From this process, the concentration and also the viscosities of the first and the second solution are already known.

List of reference numbers

1, T Stocks for inert gases

2, 2’ Pressure reduction valves for 2, 2’

3, 3’ Gas purification devices

4, 4’ Purified inert gases

7, 7’ Dry powder of ionomer-free electro catalytic particles

8, 8’ Dusts of 7, T

9, 9’ Slot dies

10, 10’ Outlet openings for electro catalytic particles, which have not been surrounded by the polymer chains on and/or near below 15a and 15b

11, 1 T Valves for recycling of electro catalytic particles

12, 12’ Second stocks for inert gas

13, 13’ Pressure reduction valves for 12, 12’

14, 14’ Vortex shakers

15 Flat film

15a 1 ^st surface of 15

15b 2 ^nd surface of 15

17, 17’ Inlet opening for 15

18, 18’ Outlet opening for 25

19, 19’ Glass bottles

20, 20’ Inlet pipes

21, 2T Stoppers

22, 22’ Outlet pipes

23, 23’ Directing zones

24, 24’ Cooling or drying device

25 Flat film with seeded electro catalytic particles

25a 1 ^st film surface of 25

25b 2 ^nd film surface of 25

26, 26’ Gas purification devices

27, 27’ Pressure reduced and purified inert gases

28, 28’ Valves for 27, 27’

29 Electro-catalyzed ion exchange membrane

40 Third mass flow containing a hollow fiber forming mass

48, 48’ Three-way valves 60, 60’ Fill levels of 7, T in 19, 19’ or in 63, 63’

61 , 6T Vibrating screens

63, 63’ Funnels

64, 64’ Pressure compensating valves

65, 65’ Drop shaft

84 1 ^st carbon paper 84

84b 1 ^st surface of 84

86 Surface fibers of 84

88 2 ^nd carbon paper

88a 1 ^st surface of 88

86’ Surface fibers of 88

94, 94’ Counter-rotating guiding rolls

95 Unit of 25 with successively applied 84 and 88

96 Unit of 25 with simultaneously applied 84 and 88

200 Device for steps b) and c) with 15 and dispersing method (2)

400 Device for steps b) and c) with 15 and dispersing method (3)

800 Spinning and electro-catalyzing nozzle

812 Base body of 800

804 Central bore of 800 for fitting of 850

808 Inlet bore of 800 for 8

823 Directing zone for electro catalytic particles against 857

824 Cooling or drying device

840 Inlet bore of 800 for hollow fiber-forming mass 40

808’ Inlet bore of 800 for 8’

838 Ring passage bore

841 Ring passage bore

838’ Ring passage bore

850 Porous hollow fiber

851 Gas impermeable disc

852 Diameter of 851

853 Height of 851

854 Protruding length of gas-permeable 850

855 Length of 850 within 804

856 Shell surface of 860

857 Lumen surface of 860

860 As-spun hollow fiber

860a Wall of 860

823 Directing zone for electro catalytic particles against 857

823’ Directing zone for electro catalytic particles against 856

824 Cooling or drying device

896 Hollow fiber-shaped and electro-catalyzed ion exchange membrane monofilament

897 Contacted swollen electro-catalyzed membranes

901 spinneret pack

902, 902’ Electron-conducting fiber or thread

902a Contacting parts of 902 with first 896 903 Hollow fiber matt with loosely connected 896

904 Hollow fiber matt with contacted 896

905 Device for connecting 902 with an external electrical circuit

906 Spirally wound 904

907 Resilient wings of 905

908 Lock to fasten 907 of 902

100 Device comprising a mat 904

101 Cylindrical case

102 Top cap arranged directly on 103

102’ Bottom cap arranged directly on 103’

103 Electron-conducting top disc

103, 103’ Top and bottom electron-conducting discs

104, 104’ Top and bottom embeddings for 897 of 904

105, 105’ Top and bottom screws

106 External circuit for electrons consumed or produced on 110

107 External circuit for electrons consumed or produced on 111

108 Length of electro-catalyzed 110 of 897

109, 109’ Length of not electro-catalyzed 110 of 897

110 Shell surface of 897

111 Lumen surface of 897

112 Inlet terminal for educts to be reacted on 110

113 Outlet terminal for products from the reaction at 110 and for non-reacted educts

114 Inlet terminal for educts to be reacted on 111

115 Outlet terminal for products from the reaction at 111 and for non-reacted educts

116 Top flange of 101

116’ Bottom flange of 101

117 Gas and liquid tight passage for electrons which are generated or consumed by 110

118, 118’ Holes in 103, 103’

119, 119’ Diameter of 118, 118’

120, 120’ Gas and liquid tight passage for electrons which are generated or consumed by 111

121 O-ring for liquid- and gas-tight connection of 103 with 102

12T O-ring for liquid- and gas-tight connection of 103’ with 102’

122 O-ring for liquid- and gas-tight connection of 103 with 116

122’ O-ring for liquid- and gas-tight connection of 103’ with 116’

123 Groove for 121

124 Holes for 105