A method for producing a catalyst-coated membrane includes: producing and/or providing at least one first ink with a first ink composition, comprising supported catalyst particles, a proton-conductive ionomer, and a dispersing agent, the content of the supported catalyst particles in the composition remaining below the content of the proton-conductive ionomer; unwinding a web-shaped proton-conductive membrane material which is provided on a roll; applying at least one layer of the first ink onto at least one section of the membrane material using a first application tool; and sputtering a catalyst powder consisting of or comprising catalyst particles onto a surface of the outermost ink layer facing away from the membrane material using a sputtering device.

A method for producing a catalyst-coated membrane includes: producing and/or providing at least one first ink with a first ink composition, comprising supported catalyst particles, a proton-conductive ionomer, and a dispersing agent, the content of the supported catalyst particles in the composition remaining below the content of the proton-conductive ionomer; unwinding a web-shaped proton-conductive membrane material which is provided on a roll; applying at least one layer of the first ink onto at least one section of the membrane material using a first application tool; and sputtering a catalyst powder consisting of or comprising catalyst particles onto a surface of the outermost ink layer facing away from the membrane material using a sputtering device.

A layer system (1) for coating a bipolar plate (2), including at least one cover layer (1a) made of tin oxide, wherein at least one metal oxide of the group comprising tantalum oxide, niobium oxide, titanium oxide, zirconium oxide, and hafnium oxide is homogenously dissolved in the tin oxide, and the electric conductivity of the cover layer (1a) is greater than or equal to 10.sup.2 S/cm. A bipolar plate (2, 2′) is also provided with an anode side and a cathode side, comprising a substrate (2a, 2a′) and such a layer system (1), and to a fuel cell (10) or an electrolyzer comprising such a bipolar plate (2, 2′).

A layer system (1) for coating a bipolar plate (2), including at least one cover layer (1a) made of tin oxide, wherein at least one metal oxide of the group comprising tantalum oxide, niobium oxide, titanium oxide, zirconium oxide, and hafnium oxide is homogenously dissolved in the tin oxide, and the electric conductivity of the cover layer (1a) is greater than or equal to 10.sup.2 S/cm. A bipolar plate (2, 2′) is also provided with an anode side and a cathode side, comprising a substrate (2a, 2a′) and such a layer system (1), and to a fuel cell (10) or an electrolyzer comprising such a bipolar plate (2, 2′).

Provided is a catalyst for electrode that has excellent catalytic activity and that is capable of contributing toward lower PEFC costs. This catalyst for electrode includes: a hollow carbon support having nanopores with a pore diameter of 1 to 20 nm; and a plurality of catalyst particles supported on the support. The catalyst particles are supported both inside and outside the nanopores of the support, are composed of (zerovalent) Pt, and when analysis of the particle size distribution of the catalyst particles is performed using three-dimensional, reconstructed images obtained through STEM-based electron tomography measurement, the percentage of catalyst particles supported inside the nanopores is 50% or more.

A membrane-electrode assembly including a polymer electrolyte membrane, and electrocatalyst layers disposed on both surfaces of the polymer electrolyte membrane, with a total light transmittance measured after delamination of both the electrocatalyst layers by using an adhesive member is 40% or less. The total light transmittance is at an electrocatalyst layer located part, when a total light transmittance at an electrocatalyst layer non-located part is taken to be 100%. The viscous member has an adhesive force of 3 N/10 mm or more when measured by pulling the viscous member adhered to a stainless steel in a 180°angle direction relative to the stainless steel, for delamination from the stainless steel.

A membrane-electrode assembly including a polymer electrolyte membrane, and electrocatalyst layers disposed on both surfaces of the polymer electrolyte membrane, with a total light transmittance measured after delamination of both the electrocatalyst layers by using an adhesive member is 40% or less. The total light transmittance is at an electrocatalyst layer located part, when a total light transmittance at an electrocatalyst layer non-located part is taken to be 100%. The viscous member has an adhesive force of 3 N/10 mm or more when measured by pulling the viscous member adhered to a stainless steel in a 180°angle direction relative to the stainless steel, for delamination from the stainless steel.

A washing device includes executors for executing a normal washing step and a reverse washing step before executing a plate opening step and a cake peeling step. The normal washing step is a step for supplying a washing water to a filter chamber, allowing the washing water to pass through a cake, and then discharging the washing water from filtrate discharge outlets. The reverse washing step is a step for supplying a washing water from the filtrate discharge outlet(s) to the filter chamber, allowing the washing water to pass through the cake, and then discharging the washing water from the filtrate discharge outlet(s) which are different from the filtrate discharge outlet(s) from which the washing water is supplied. The thickness of the electrode catalyst precursor-containing cake at the time of the injection step is adjusted to that of a range that has been previously and experimentally determined.

The present disclosure relates to antioxidant for a polymer electrolyte membrane fuel cell electrode catalyst, which includes cerium hydrogen phosphate (HCe.sub.2(PO.sub.4).sub.3(H.sub.2O)) in the form of a nanofiber, and an electrode and a membrane-electrode assembly including the same. The electrode for a polymer electrolyte membrane fuel cell of the present disclosure, wherein the antioxidant is dispersed, can improve the mechanical strength of an electrode catalyst layer and can minimize deterioration of chemical durability even after long-term operation. And, a fuel cell including the same can exhibit high output performance and can operate stably even after long-term operation.

The present disclosure relates to antioxidant for a polymer electrolyte membrane fuel cell electrode catalyst, which includes cerium hydrogen phosphate (HCe.sub.2(PO.sub.4).sub.3(H.sub.2O)) in the form of a nanofiber, and an electrode and a membrane-electrode assembly including the same. The electrode for a polymer electrolyte membrane fuel cell of the present disclosure, wherein the antioxidant is dispersed, can improve the mechanical strength of an electrode catalyst layer and can minimize deterioration of chemical durability even after long-term operation. And, a fuel cell including the same can exhibit high output performance and can operate stably even after long-term operation.