This disclosure provides systems, methods, and apparatus related to electrode structures. In one aspect, a method includes: providing an electrode layer comprising a ceramic, the ceramic being porous; providing a catalyst precursor, the catalyst precursor being a cathode catalyst precursor or an anode catalyst precursor; infiltrating the catalyst precursor in a first side of the electrode layer; after the infiltrating operation, heating the electrode layer to about 750 C. to 950 C., the catalyst precursor forming a catalyst, the catalyst being a cathode catalyst or an anode catalyst; infiltrating the catalyst precursor in the first side of the electrode layer; after the infiltrating operation, heating the electrode layer to about 300 C. to 700 C., the catalyst precursor forming the catalyst, the catalyst being the cathode catalyst or the anode catalyst.

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.

A sodium ion battery electrode material is disclosed, the electrode material including a conductive porous material or a conductive porous composite. A sodium accommodating pore is defined inside the electrode material, effective pore diameter size for sodium ion storage in the sodium accommodating pore is in a range of 0.2-50 nm. A method for preparing the conductive porous composite and a sodium ion battery electrode are also provided.

An electrode catalyst which is for a hydrogen fuel cell anode and in which Pt particles and WO.sub.3 particles are carried on carbon carriers, wherein the WO.sub.3 particles have a monocline system crystalline structure.

Novel active supports, novel catalysts, and methods of preparing active supports using a sacrificial template particles and methods of preparing the same are all described.

Nanostructured materials, and methods and apparatus for their production are provided. Nanostructured materials comprise nanofibers having nanoparticles deposited along the outer surface thereof. The size of the nanofibers and nanoparticles, and the spacing of such nanoparticles along the nanofibers may be controlled over a wide range. Nanostructured materials may comprise a plurality of such nanofibers interwoven together to form fiber cloth-like materials. Many materials may be used to form the nanofibers including polymer nanofiber materials (e.g., polyvinyl alcohol (PVA) polyvinylpyrrolidone (PVP), etc.) along with compatible nanoparticle materials (e.g., salts or other crystallizable materials).

A membrane/electrode assembly of a fuel cell using a film obtained by molding a mixture in which a synthetic resin and a solvent are mixed with fullerene nanowhisker/nanofiber nanotubes supporting a catalyst or including a catalyst in fullerene crystals, wherein the fullerene nanowhisker/nanofiber nanotubes are obtained by uniformly stirring and mixing a solution containing a first solvent having fullerene dissolved therein, and a second solvent in which fullerene is less soluble than that in the first solvent, in a thin film fluid formed between processing surfaces arranged to be opposite to each other so as to be able to approach to and separate from each other, at least one of which rotates relative to the other, and the resultant fullerene nanowhisker/nanofiber nanotubes are heated at 300 C. to 1000 C. in a vacuum heating furnace.

A catalyst particle (1) for a fuel cell according to the present invention includes: a metal particle (2) composed of either one of metal other than noble metal and an alloy of the metal other than the noble metal and the noble metal; and a noble metal layer (3) that is provided on a surface of the metal particle and has a thickness of 1 nm to 3.2 nm. By the fact that the catalyst particle for a fuel cell has such a configuration, the catalyst particle can enhance catalytic activity while reducing an amount of the noble metal. The catalyst particle (1) for a fuel cell according to the present invention can enhance the catalytic activity while reducing the amount of the noble metal.

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 method for uniformly forming a nickel-metal alloy catalyst in a fuel electrode of a solid oxide electrolysis cell is provided. Specifically, before the nickel-metal alloy catalyst is formed, a metal oxide is uniformly distributed on nickel oxide contained in the fuel electrode through infiltration of a metal oxide precursor solution and hydrolysis of urea.