A catalyst includes a mesoporous material and catalytic metal particles supported at least within the mesoporous material and containing platinum and a metal different from platinum. The mesoporous material has mesopores with a mode radius of 1 to 25 nm and a pore volume of 1.0 to 3.0 cm.sup.3/g before supporting of the catalytic metal particles, and has an average particle size of greater than or equal to 200 nm. A molar ratio of the metal different from platinum and contained in the catalytic metal particles relative to all metals contained in the catalytic metal particles is greater than or equal to 0.25, and among the catalytic metal particles, a volume ratio of catalytic metal particles having a particle size of greater than or equal to 20 nm is less than or equal to 10%.

A method of preparing a catalyst for a fuel cell includes no carbon support. The method of preparing a catalyst for a fuel cell includes preparing a first metal nanoparticle having a polyhedral shape, growing a second metal along the edge of the first metal nanoparticle, and removing the first metal nanoparticle.

Provided is a method for producing metal nanoparticles, which enables metal nanoparticles to be more conveniently produced.

The method for producing metal nanoparticles includes spraying and drying a mixture to form metal nanoparticles, the mixture containing a metal salt and at least one solvent selected from alcohols having 1 or more and 5 or less carbon atoms.

A fuel cell catalyst material includes metal catalyst particles formed of a metal material and a carbon-based coating composition at least partially coating at least some of the metal catalyst particles. The carbon-based coating composition includes a carbon network. The carbon-based coating composition is doped with a dopant. The carbon-based coating composition includes a number of defects formed by one or more vacated carbon atoms in the carbon network.

The invention includes a method of making a catalytic electrode for a metal-air cell in which a carbon-catalyst composite is produced by heating a manganese compound in the presence of a particulate carbon material to form manganese oxide catalyst on the surfaces of the particulate carbon, and then adding virgin particulate carbon material to the carbon-catalyst composite to produce a catalytic mixture that is formed into a catalytic layer. A current collector and an air diffusion layer are added to the catalytic layer to produce the catalytic electrode. The catalytic electrode can be combined with a separator and a negative electrode in a cell housing including an air entry port through which air from outside the container can reach the catalytic electrode.

A method of operating a fuel cell having an anode, a cathode and a polymer electrolyte membrane disposed between the anode and the cathode, includes feeding the anode with an impure hydrogen stream having low levels of carbon monoxide up to 5 ppm, and wherein the anode includes an anode catalyst layer including a carbon monoxide tolerant catalyst material, wherein the catalyst material includes: (i) a binary alloy of PtX, wherein X is a metal selected from the group consisting of rhodium and osmium, and wherein the atomic percentage of platinum in the alloy is from 45 to 80 atomic % and the atomic percentage of X in the alloy is from 20 to 55 atomic %; and (ii) a support material on which the PtX alloy is dispersed; wherein the total loading of platinum group metals (PGM) in the anode catalyst layer is from 0.01 to 0.2 mgPGM/cm.sup.2.

A platinum/black phosphorus-carbon sphere methanol fuel cell anode catalyst and preparation method thereof including the following steps: (1) dispersing a black phosphorus solid in an organic solvent to obtain a single or a few layers of black phosphorus dispersion with set concentration; (2) mixing the dispersion with glucose and stirring until dissolved; (3) performing a hydrothermal reaction on the solution to obtain an aqueous solution of the composite material containing a carbon core black phosphorus shell structure; (4) uniformly mixing the aqueous solution with an ethylene glycol solution of sodium chloroplatinate, adjusting the pH, then reducing the platinum on the surface by using a microwave irradiation heating method; and (5) filtering, washing and drying the obtained composite material to obtain a platinum/black phosphorus-carbon sphere composite material. The composite material is applied to a direct methanol fuel cell anode catalyst, the catalytic and stability performance of which are greatly improved.

A metal-air battery includes: an air electrode; a negative electrode containing a metal; and an electrolyte having ion conductivity. The air electrode includes: a co-continuous body having a three-dimensional network structure in which a plurality of nanostructures is split and integrated; and mesoporous carbon supported on the co-continuous body.

A method of operating a fuel cell having an anode, a cathode and a polymer electrolyte membrane disposed between the anode and the cathode, includes feeding the anode with an impure hydrogen stream having low levels of carbon monoxide up to 5 ppm, and wherein the anode includes an anode catalyst layer including a carbon monoxide tolerant catalyst material, wherein the catalyst material includes: (i) a binary alloy of PtX, wherein X is a metal selected from the group consisting of rhodium and osmium, and wherein the atomic percentage of platinum in the alloy is from 45 to 80 atomic % and the atomic percentage of X in the alloy is from 20 to 55 atomic %; and (ii) a support material on which the PtX alloy is dispersed; wherein the total loading of platinum group metals (PGM) in the anode catalyst layer is from 0.01 to 0.2 mgPGM/cm.sup.2.

Provided are positive electrode active material particles for a secondary battery which include a lithium cobalt oxide, a coating layer including element A and formed on a surface of particles of the lithium cobalt oxide, and a dopant containing element B which is substituted in the lithium cobalt oxide, wherein the element A and the element B are each independently at least one selected from the group consisting of aluminum (Al), titanium (Ti), magnesium (Mg), zirconium (Zr), barium (Ba), calcium (Ca), tantalum (Ta), niobium (Nb), and molybdenum (Mo), and a molar ratio of the element A in the coating layer:the element B of the dopant is greater than 1:1 to 10:1.