A CoVO.sub.x composite electrode and method of making is described. The composite electrode comprises a substrate with an average 0.5-5 ?m thick layer of CoVO.sub.x having pores with average diameters of 2-200 nm. The method of making the composite electrode involves contacting the substrate with an aerosol comprising a solvent, a cobalt complex, and a vanadium complex. The CoVO.sub.x composite electrode is capable of being used in an electrochemical cell for water oxidation.

A CoVO.sub.x composite electrode and method of making is described. The composite electrode comprises a substrate with an average 0.5-5 ?m thick layer of CoVO.sub.x having pores with average diameters of 2-200 nm. The method of making the composite electrode involves contacting the substrate with an aerosol comprising a solvent, a cobalt complex, and a vanadium complex. The CoVO.sub.x composite electrode is capable of being used in an electrochemical cell for water oxidation.

Disclosed are an electrode including a porous substrate, a membrane-electrode assembly for a fuel cell including the same and a method of manufacturing the same. In the method of manufacturing the membrane-electrode assembly, the amount of a catalyst that is loaded depending on the position is applied in a gradational manner, thus efficiently using the catalyst, thereby reducing costs owing to the use of a decreased amount of the metal catalyst. Further, the membrane-electrode assembly includes the electrode including a porous substrate, thus making it easy to select hot-pressing conditions and increasing processing efficiency. The porous substrate is hydrophobic and the pore size in the electrode is not decreased compared to conventional electrodes, thus reducing flooding and generating various operation regions. The electrode including the porous substrate can minimize electrode loss, thus improving electrode durability.

A method for preparing a support for an electrode catalyst including forming first and second polymer layers having charges different from each other on a surface of a carbon support and carbonizing the result, wherein the polymers included in the first and the second polymer layers are an aromatic compound including a heteroatom, and the first or the second polymer includes a pyridine group.

The catalytic electrode of the present invention does not cause electron transfer resistance, unlike conventional catalytic electrodes coated with Nafion or the like, and thus can achieve significantly high electron transfer efficiency. Accordingly, the catalytic electrode can have high power density, and thus has excellent physical properties.

A gas diffusion layer for a metal-air battery, the gas diffusion layer including: a porous layer including non-conductive fiber structures, a conductive carbon layer including a carbon material that is disposed on a surface of a non-conductive fiber structure of the plurality of non-conductive fiber structures.

The present invention relates to a cathode for a metal-air battery, a method for manufacturing the same, and a metal-air battery including the same. The cathode comprises a needle-shaped core including two or more species of metals selected from the group consisting of nickel, cobalt, manganese, zinc, iron, copper, and chrome, or a cobalt oxide; and a flake-shaped shell including an oxide containing two or more species of metals selected from the group consisting of nickel, cobalt, manganese, zinc, iron, copper, and chrome or a cobalt oxide. As such, the core-shell structure may lead to a reduction in the charge voltage of the metal-air battery as well as the taking of the good capacity characteristics of the transition metal oxide. Further, according to the present invention, the cathode for a metal-air battery may be produced without adding carbon or binder.

In some embodiments, a solid oxide fuel cell comprising an anode, an electrolyte, cathode barrier layer, a nickelate composite cathode separated from the electrolyte by the cathode barrier layer, and a cathode current collector layer is provided. The nickelate composite cathode includes a nickelate compound and second oxide material, which may be an ion conductor. The composite may further comprise a third oxide material. The composite may have the general formula (Ln.sub.uM1.sub.vM2.sub.s).sub.n+1(Ni.sub.1-tN.sub.t).sub.nO.sub.3n+1-A.sub.1-xB.sub.xO.sub.yC.sub.wD.sub.zCe.sub.(1-w-z)O.sub.2-, wherein A and B may be rare earth metals excluding ceria.

In some embodiments, a solid oxide fuel cell comprising an anode, an electrolyte, cathode barrier layer, a nickelate composite cathode separated from the electrolyte by the cathode barrier layer, and a cathode current collector layer is provided. The nickelate composite cathode includes a nickelate compound and second oxide material, which may be an ion conductor. The composite may further comprise a third oxide material. The composite may have the general formula (Ln.sub.uM1.sub.vM2.sub.s).sub.n+1(Ni.sub.1-tN.sub.t).sub.nO.sub.3n+1-A.sub.1-xB.sub.xO.sub.y-C.sub.wD.sub.zCe.sub.(1-w-z)O.sub.2-, wherein A and B may be rare earth metals excluding ceria.

A method for producing a fuel cell catalyst layer, which is able to allow an ionomer to sufficiently penetrate to the inside of the fine pores of a support with fine pores. The method is a method for producing a fuel cell catalyst layer in which a catalyst is supported on the support with fine pores and is coated with an ionomer, the method comprising: hydrophilizing a surface of the support by use of nitric acid, and dispersing the support, the catalyst and the ionomer by use of a ball mill after the hydrophilizing, wherein the amount of acidic functional groups per specific surface area of the support is set to 1.79 mol/m.sup.2 or more in the hydrophilizing.