Substrates for producing oxygen electrodes, oxygen electrodes, electrochemical devices and productions methods are provided. Substrates include an intermediate microporous layer (MPL) attached to a porous transport layer (PTL) to interface between the PTL and the catalytic layer deposited on the MPLto provide microstructure compatibility, improved adhesion and better performance of the oxygen electrode produced therefrom. The MPL corresponds to the PTL with respect to the types of metallic material, to provide good electric conductivity, while the metal particle sizes of the MPL are selected to modify the pore sizes of the PTL to reach a predefined pore size distribution of the substratewhich best supports printing, adhesion and performance of the catalyst layer on the substrate. Electrochemical devices such as fuel cells, electrolyzers and reversible devices may include the oxygen electrodes, which may be optimized for the specific application.

A catalyst which is suitable for use in an anode of a fuel cell. The catalyst comprises, in at least partially reduced form, (i) nickel and (ii) molybdenum and, optionally, (iii) rhenium and/or (iv) at least one transition metal which is different from nickel, molybdenum and rhenium, supported on (v) electrically conductive carbon modified with one or more elements selected from the lanthanides, yttrium, tin and titanium. The weight ratio (i):((ii)+(iii)+(iv)) is at least 2:1.

A solid oxide fuel cell comprising an electrolyte, an anode and a cathode. In this fuel cell at least one electrode has been modified with a promoter using gas phase infiltration.

In some examples, a fuel cell comprising an anode; an electrolyte; cathode barrier layer; and a nickelate composite cathode separated from the electrolyte by the cathode barrier layer; and a cathode current collector layer. The nickelate composite cathode includes a nickelate compound and an ionic conductive material, and the nickelate compound comprises at least one of Pr.sub.2NiO.sub.4, Nd.sub.2NiO.sub.4, (Pr.sub.uNd.sub.v).sub.2NiO.sub.4, (Pr.sub.uNd.sub.v).sub.3Ni.sub.2O.sub.7, (Pr.sub.uNd.sub.v).sub.4Ni.sub.3O.sub.10, or (Pr.sub.uNd.sub.vM.sub.w).sub.2NiO.sub.4, where M is an alkaline earth metal doped on an Asite of Pr and Nd. The ionic conductive material comprises a first co-doped ceria with a general formula of (A.sub.xB.sub.y)Ce.sub.1-x-yO.sub.2, where A and B of the first co-doped ceria are rare earth metals. The cathode barrier layer comprises a second co-doped ceria with a general formula (A.sub.xB.sub.y)Ce.sub.1-x-yO.sub.2, where at least one of A or B of the second co-doped ceria is Pr or Nd.

A known method for producing porous graphitized carbon material covered with metal nanoparticles involves infiltrating a porous template framework of inorganic material with a carbon precursor. After thermal treatment of the precursor, the template is removed and the particulate porous carbon material is covered with a catalytically active substance. According to the invention, in order to keep the proportion of the noble metal loading at a low level, the thermal treatment of the precursor first involves carbonization, and the material is not graphitized into graphitized, particulate, porous carbon material until the template has been removed. The graphitized carbon material has a hierarchical pore structure with a pore volume of at least 0.5 cm.sup.3/g and at least 75% of the pore volume is apportioned to macropores with, size 100 to 5000 nm. Before covering with catalytically active substance, the carbon material is subjected to an activation treatment in an oxidizing atmosphere.

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 catalyst carrier production process includes a step (a) of mixing a transition metal compound (1), a nitrogen-containing organic compound (2), and a solvent to provide a catalyst carrier precursor solution; a step (b) of removing the solvent from the catalyst carrier precursor solution; and a step (c) of thermally treating a solid residue obtained in the step (b) at a temperature of 500 to 1100 C. to provide a catalyst carrier; wherein the transition metal compound (1) is partly or wholly a compound including a transition metal element (M1) selected from the group 4 and 5 elements of the periodic table as a transition metal element; and at least one of the transition metal compound (1) and the nitrogen-containing organic compound (2) includes an oxygen atom.

A non-carbon support particle is provided for use in electrocatalyst. The non-carbon support particle consists essentially of titanium dioxide and ruthenium dioxide. The titanium and ruthenium can have a mole ratio ranging from 1:1 to 9:1 in the non-carbon support particle. Also disclosed are methods of preparing the non-carbon support and electrocatalyst taught herein.

The present invention provides a substrate film that has a catalyst coating liquid having good coating properties when producing a membrane electrode assembly, has a catalyst layer and support film having good release properties after the catalyst layer is transferred to an electrolyte membrane using a catalyst transfer sheet, and does not contaminate the catalyst layer. Provided is a substrate film for a catalyst transfer sheet, said substrate film being formed by introducing fluorine atoms to at least one surface of a base film formed from one or more types of polymers selected from the group consisting of polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyethylene napthalate, polyphenylene sulfide, polysulfones, polyether ketone, polyether ether ketone, polyimides, polyetherimide, polyamides, polyamide-imides, polybenzimidazoles, polycarbonates, polyarylates, and polyvinyl chloride, wherein the ratio, measured by X-ray photoelectron spectroscopy, of the number of fluorine atoms/the number of carbon atoms in the surface to which the fluorine atoms are introduced, i.e. the modified surface, is 0.02-1.9, inclusive.