A catalyst carrier, an electrode catalyst, an electrode including the catalyst, a membrane electrode assembly including the electrode, and a fuel cell including the membrane electrode assembly. The catalyst carrier includes a carbon material having a chain structure including a chain of carbon particles and an alumina-carbon composite particle in which a carbon particle encloses an alumina particle, the alumina-carbon composite particle is contained in the carbon material, and the catalyst carrier has a BET specific surface area of 450 to 1100 m.sup.2/g.

A method for producing a catalyst supporting a metal or an alloy on a support, including: independently controlling a temperature of a first supercritical fluid to be first temperature, the first supercritical fluid containing a precursor of the metal or precursor of the alloy that is dissolved in a supercritical fluid; independently controlling a temperature of the support to be a second temperature higher than the temperature of the first supercritical fluid; and supplying the first supercritical fluid controlled to the first temperature to the support, to cause the metal or the alloy to be supported on the support.

Provided is a carbon-fiber nonwoven cloth with low resistance to gases or liquids passing through, and low resistance in the thickness direction to heat or electricity, which is particularly appropriate for a gas diffusion electrode of a polymer electrolyte fuel cell; the cloth having an air gap with a diameter of at least 20 μm, at least some of the carbon fibers being continuous from one surface to the other surface, and the apparent density being 0.2-1.0 g/cm.sup.3, or, having an air gap with a diameter of at least 20 μm and at least some of the carbon fibers being mutually interlaced, and further, at least some of the carbon fibers being oriented toward the thickness direction and the apparent density being 0.2-1.0 g/cm.sup.3.

Disclosed is a cathode catalyst layer for fuel cells including heat-treated ordered mesoporous carbon, wherein the heat-treated ordered mesoporous carbon is present in an amount of 1% by weight to 15% by weight, with respect to the total weight of the cathode catalyst layer for fuel cells, and a method of manufacturing the same.

The present invention provides a metal composite carbon material that provides a large contact interface between a fluid and metal fine particles and that can exhibit high catalytic performance when used as a catalyst, having metal fine particles supported in a continuous porous structure in which a carbon skeleton and voids form respective continuous structures, the continuous porous structure having a structural period of larger than 2 nm and 10 μm or smaller.

The present invention relates to an electrode catalyst for a fuel cell that includes a carbon support (11) having pores (13) and catalyst particles containing platinum or a platinum alloy supported on the carbon support (11). The pores (13) of the carbon support (11) have a mode size of pores (13) in a range of 2.1 nm to 5.1 nm. A total pore volume of the pores (13) of the carbon support (11) is in a range of 21 cm.sup.3/g to 35 cm.sup.3/g. A distance between the catalyst particles and a surface of the carbon support (11) is in a range of 2.0 nm to 12 nm as a distance of a 50% cumulative frequency.

A double-layer anode structure on a pretreated porous metal substrate and a method for fabricating the same, for improving the redox stability and decreasing the anode polarization resistance of a SOFC. The anode structure includes: a porous metal substrate of high gas permeability; a first porous anode functional layer, formed on the porous metal substrate by a high-voltage high-enthalpy Ar—He—H.sub.2—N.sub.2 atmospheric-pressure plasma spraying process; and a second porous anode functional layer, formed on the first porous anode functional layer by a high-voltage high-enthalpy Ar—He—H.sub.2—N.sub.2 atmospheric-pressure plasma spraying and hydrogen reduction. The first porous anode functional layer is composed a redox stable perovskite, the second porous anode functional layer is composed of a nanostructured cermet. The first porous anode functional layer is also used to prevent the second porous anode functional layer from being diffused by the composition elements of the porous metal substrate.

A method of growing crystals on two-dimensional layered material is provided that includes reversibly hydrogenating a two-dimensional layered material, using a controlled radio-frequency hydrogen plasma, depositing Pt atoms on the reversibly hydrogenated two-dimensional layered material, using Atomic Layer Deposition (ALD), where the reversibly hydrogenated two-dimensional layered material promotes loss of methyl groups in an ALD Pt precursor, and forming Pt-O on the reversibly hydrogenated two-dimensional layered material, using combustion by O.sub.2, where the Pt-O is used for subsequent Pt half-cycles of the ALD process, where growth of Pt crystals occurs.

A porous carbon sheet contains a carbon fiber and a binding material, wherein layers are obtained in a section spanning from a plane closest to one of the surfaces and having 50% of the mean fluorine intensity to a plane closest to the other surface and having 50% of the mean fluorine intensity by dividing this section evenly into three in an orthogonal direction to the carbon sheet plane; among the layer close to one of the surfaces and the layer close to the other surface, the layer having the larger layer mean fluorine intensity is designated layer X, the layer having the smaller one is designated layer Y, and the layer between the layer X and the layer Y is designated layer Z; and the layer mean fluorine intensities decrease in the order: layer X, layer Y, and layer Z.

The present invention is to provide a method for producing a catalyst for fuel cells with excellent durability, and a fuel cell comprising a catalyst for fuel cells produced by the production method. Disclosed is a method for producing a catalyst for fuel cells, the catalyst comprising fine catalyst particles, each of which comprises a palladium-containing core particle and a platinum-containing outermost layer covering the core particle, and carbon supports on which the fine catalyst particles are supported, wherein the method comprises the steps of: preparing carbon supports on which palladium-containing particles are supported; fining the carbon supports; and covering the palladium-containing particles with a platinum-containing outermost layer after the fining step.