Disclosed are: a membrane-electrode assembly having enhanced adhesion and interfacial durability between a polymer electrolyte membrane and electrodes; and a method for manufacturing a membrane-electrode assembly, in which, in forming electrodes by directly coating a catalyst slurry on a polymer electrolyte membrane, adhesion and interfacial durability between the polymer electrolyte membrane and the electrodes can be enhanced without a separate additional step, thus improving both the durability and the productivity of the membrane-electrode assembly. The method comprises the steps of: dispersing a catalyst and an ion conductor in a dispersion medium to obtain a catalyst slurry; applying the catalyst slurry onto a polymer electrolyte membrane; and drying the catalyst slurry applied onto the polymer electrolyte membrane to form an electrode. The dispersion medium is a solvent capable of forming a plurality of grooves on a surface of the polymer electrolyte membrane, and, when the electrode is formed through the drying step, at least some of the grooves are filled with the catalyst, the ion conductor, or a mixture thereof.

The present invention provides a catalyst layer, a catalyst layer ink and a membrane-electrode assembly which enable provision of fuel cells with high power efficiency. The catalyst layer of the present invention comprises a carbon alloy catalyst and an ion exchange polymer which comprises at least one species of units having a cyclic ether structure selected from the group consisting of units represented by the formula (u11), units represented by the formula (u12), units represented by the formula (u21), units represented by the formula (u22) and units represented by the formula (u24).

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Membrane electrode assembly and method for fabricating the same. In one embodiment, the method may involve providing an anion exchange membrane and then applying catalyst coatings to opposing surfaces of the anion exchange membrane, whereby a membrane electrode assembly may be formed. Next, the membrane electrode assembly may be subjected to a two-part treatment process. In a first part of the process, the membrane electrode assembly may be swelled, at room temperature, by exposure to an aqueous ethanol solution vapor while being retained under tension in a frame. The aqueous ethanol solution vapor may be, for example, 80:20 by volume ethanol and water. In a second part of the process, the swollen membrane electrode assembly may be removed from the frame and then pressed, at room temperature, between two plates. A layer of rubber and a layer polytetrafluoroethylene may be placed between each plate and the swollen membrane electrolyte assembly.

A catalyst-coated membrane (CCM) for use in a water electrolyser, having a laminate structure comprising: a first layer comprising a first membrane component having a cathode catalyst layer disposed on a first face thereof; a second layer comprising a second membrane component having an anode catalyst layer disposed on a first face thereof; and an intermediate layer disposed between the first and second layers, comprising a third membrane component having a recombination catalyst layer disposed on a first face thereof is disclosed. The CCM is useful within a water electrolyser. The recombination catalyst layer reduces the risk associated with hydrogen crossover and allows thinner membranes with lower resistance to be used.

Disclosed are a method of manufacturing a membrane-electrode assembly and a membrane-electrode assembly manufactured using the same. The method includes forming a laminated structure, and treating the laminated structure, for example, by drying and heat treating. The laminated structure includes a release film, an anode layer, a porous support layer, and a cathode layer.

An electrolyte membrane of a membrane-electrode assembly is formed by a manufacturing method yielding a membrane with improved chemical durability. The manufacturing method includes preparing an antioxidant solution, mixing the antioxidant solution and a first ionomer dispersion solution, drying the mixture to produce a composite having an antioxidant and a first ionomer surrounding the antioxidant, introducing and mixing the composite with a second ionomer dispersion solution, and applying that mixture to a substrate and drying the mixture to manufacture an electrolyte membrane. The resulting electrolyte membrane includes the composite having an antioxidant in an ionic state and a first ionomer surrounding the antioxidant.

A membrane electrode assembly can include an anode layer. The anode layer can include a first layer, and a second layer. The second layer can include a cerium oxide. A method of assembling a membrane electrode assembly can include provision of a membrane, a first layer, and a second layer. The second layer can include a cerium oxide. The first layer can be disposed on the second layer to form an anode layer. The anode layer can be disposed on an anode side of the membrane.

Among the various aspects of the present disclosure is the provision of method of inducing or providing a pH gradient in electrochemical or chemical systems. Briefly, the pH gradient is induced by use of coated particles or films with an ion exchange ionomer.

A method for production of a fuel cell includes:

a) Preparing a plurality of catalyst pastes which differ from each other at least in regard to one parameter influencing the catalytic activity,

b) Filling of at least two of the plurality of catalyst pastes into a first application means having a number of chambers corresponding to the number of catalyst pastes being filled, where only one of the catalyst pastes is filled into each of the chambers,

c) Filling of at least two of the plurality of catalyst pastes into a second application means having a number of chambers corresponding to the number of catalyst pastes being filled, where only one of the catalyst pastes is filled into each of the chambers,

d) Coating of a first side of a foil web of an electrolyte membrane which is moved past the first application means and the second application means by means of the first application means,

e) Coating of a second side of the foil web by means of the second application means,

f) Cutting of the resulting coated electrolyte membrane from the foil web and rotating of the electrolyte membrane by 90° with respect to a delivery direction of the foil web,

g) Placing of the electrolyte membrane between two flow field plates with a gradient in regard to the parameter which is oriented perpendicular to the flow field, and

h) Pressing together the flow field plates.

A composite includes a fluorinated polymer and nanoparticles of a metal salt. The metal salt has a solubility product of not more than 1×10.sup.−4. The fluorinated polymer includes a fluorinated polymer backbone chain and a plurality of groups represented by formula —SO.sub.2X, in which each X is independently —NZH, —NZSO.sub.2(CF.sub.2).sub.1-6SO.sub.2X′, —NZ[SO.sub.2(CF.sub.2).sub.dSO.sub.2NZ].sub.1-10SO.sub.2(CF.sub.2).sub.dSO.sub.2X′ or —OZ, and Z is independently a hydrogen, an alkali-metal cation, or a quaternary ammonium cation, X′ is independently —NZH or —OZ, and each d is independently 1 to 6. A polymer electrolyte membrane, an electrode, and a membrane electrode assembly including the composite are also provided.