Abstract: A method for producing a fuel cell electrode catalyst, including a step (I) of bringing an aqueous solution of a transition metal compound (1) into contact with ammonia and/or ammonia water to generate a precipitate (A) containing an atom of the transition metal, a step (II) of mixing at least the precipitate (A), an organic compound (B), and a liquid medium (C) to obtain a catalyst precursor liquid, and a step (IV) of subjecting the solid in the catalyst precursor liquid to heat treatment at a temperature of 500 to 1200° C. to obtain an electrode catalyst; a portion or the entirety of the transition metal compound (1) being a compound containing a transition metal element of group 4 or group 5 of the periodic table; and the organic compound (B) being at least one selected from sugars and the like.

Abstract: The present invention concerns an oxygen reduction catalyst comprising composite particles in which primary particles of a titanium compound is dispersed into a carbon structure, wherein the composite particles have titanium, carbon, nitrogen and oxygen as constituent elements, and with regard to a ratio of number of atoms of each of the elements when titanium is taken as 1, a ratio of carbon is larger than 2 and 5 or less, a ratio of nitrogen is larger than 0 and 1 or less, and a ratio of oxygen is 1 or more and 3 or less, and an intensity ratio (D/G ratio) of D band peak intensity to G band peak intensity in a Raman spectrum is in the range of 0.4 to 1.0. The oxygen reduction catalyst according to the present invention has satisfactory initial performance and excellent start-stop durability.

Abstract: 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.

Abstract: An R-T-B-based rare earth sintered magnet comprising: a rare earth element R, B, a metallic element M which includes one or more metals selected from Al, Ga and Cu, a transition metal T which includes Fe as a main component and inevitable impurities, wherein the sintered magnet includes: 13 to 15.5 atom % of R, 5.0 to 6.0 atom % of B, 0.1 to 2.4 atom % of M, and T and the inevitable impurities as a balance, and wherein the sintered magnet includes more than 0 atom % and 0.01 atom % or less of Tb as the rare earth element R.

Abstract: 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.

Abstract: In a direct-liquid fuel cell supplied directly with a liquid fuel, a process for producing an electrode catalyst for a direct-liquid fuel cell is provided which is capable of suppressing decrease in cathode potential caused by liquid fuel crossover and providing an inexpensive and high-performance electrode catalyst for a direct-liquid fuel cell. The process for producing an electrode catalyst for a direct-liquid fuel cell includes Step A of mixing at least a transition metal-containing compound with a nitrogen-containing organic compound to obtain a catalyst precursor composition, and Step C of heat-treating the catalyst precursor composition at a temperature of from 500 to 1100° C. to obtain an electrode catalyst, wherein part or entirety of the transition metal-containing compound includes, as a transition metal element, at least one transition metal element M1 selected from Group IV and Group V elements of the periodic table.

Abstract: 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 the 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.

Abstract: Provided is a method of manufacturing an alloy for an R-T-B-based rare earth sintered magnet, with which an R-T-B-based magnet having high coercive force can be obtained even when the B concentration is low and the Dy concentration is zero or extremely low. This method includes: a casting step of manufacturing a cast alloy by casting a molten alloy, a hydrogenating step of absorbing hydrogen in the cast alloy; and a dehydrogenating step of removing hydrogen from the cast alloy absorbing hydrogen in an inert gas atmosphere at a temperature lower than 550° C., wherein the molten alloy consists of B, a rare earth element R, a transition metal T essentially containing Fe, a metal element M, and unavoidable impurities, in which the R content is 13 at % to 15.5 at %, the B content is 5.0 at % to 6.0 at %, the M content is 0.1 at % to 2.4 at %, the T content is a balance, a ratio of a Dy content to the total content of the rare earth element is 0 at % to 65 at %, and the molten alloy satisfies the below formula (1).

Abstract: Provided is a process for producing a fuel cell electrode catalyst having high catalytic activity which uses a transition metal, e.g., titanium, which process comprises thermal treatment at relatively low temperature, i.e., not including thermal treatment at high temperature (calcining) step. The process for producing a fuel cell electrode catalyst comprises a step (1) of mixing at least a transition metal-containing compound, a nitrogen-containing organic compound and a solvent to provide a catalyst precursor solution; a step (2) of removing the solvent from the catalyst precursor solution; and a step (3) of thermally treating a solid residue obtained in the step (2) at a temperature of 500 to 1100° C. to provide an electrode catalyst; wherein the transition metal-containing compound is partly or wholly a compound comprising at least one transition metal element (M1) selected from the group 4 and 5 elements of the periodic table as a transition metal element.

Abstract: Provided is a process for producing a fuel cell electrode catalyst having high catalytic activity which uses a transition metal, e.g., titanium, which process comprises thermal treatment at relatively low temperature, i.e., not including thermal treatment at high temperature (calcining) step. The process for producing a fuel cell electrode catalyst comprises a step (1) of mixing at least a transition metal-containing compound, a nitrogen-containing organic compound and a solvent to provide a catalyst precursor solution; a step (2) of removing the solvent from the catalyst precursor solution; and a step (3) of thermally treating a solid residue obtained in the step (2) at a temperature of 500 to 1100° C. to provide an electrode catalyst; wherein the transition metal-containing compound is partly or wholly a compound comprising at least one transition metal element (M1) selected from the group 4 and 5 elements of the periodic table as a transition metal element.

Abstract: Provided is a method for operating a fuel cell involving supplying an electrode with a low or non-humidified gas that achieves no significant decrease of voltage as compared with when a high-humidified feed gas is used. The method for operating a fuel cell having a membrane electrode assembly includes a cathode, an anode and an electrolyte membrane interposed between both the electrodes, wherein the cathode has a layer including an oxygen reducing catalyst including composite particles which include atoms of a metal element M1, carbon, nitrogen and oxygen and in which primary particles of a compound of the metal element M1 are dispersed in a carbon structure, which method includes supplying the cathode with an oxidizing agent gas which includes an oxygen gas and which has a relative humidity at a temperature of the membrane electrode assembly of 60% or less, and supplying the anode with a fuel gas.

Abstract: The present invention concerns an oxygen reduction catalyst comprising composite particles in which primary particles of a titanium compound is dispersed into a carbon structure, wherein the composite particles have titanium, carbon, nitrogen and oxygen as constituent elements, and with regard to a ratio of number of atoms of each of the elements when titanium is taken as 1, a ratio of carbon is larger than 2 and 5 or less, a ratio of nitrogen is larger than 0 and 1 or less, and a ratio of oxygen is 1 or more and 3 or less, and an intensity ratio (D/G ratio) of D band peak intensity to G band peak intensity in a Raman spectrum is in the range of 0.4 to 1.0. The oxygen reduction catalyst according to the present invention has satisfactory initial performance and excellent start-stop durability.

Abstract: In a direct-liquid fuel cell supplied directly with a liquid fuel, a process for producing an electrode catalyst for a direct-liquid fuel cell is provided which is capable of suppressing decrease in cathode potential caused by liquid fuel crossover and providing an inexpensive and high-performance electrode catalyst for a direct-liquid fuel cell. The process for producing an electrode catalyst for a direct-liquid fuel cell includes Step A of mixing at least a transition metal-containing compound with a nitrogen-containing organic compound to obtain a catalyst precursor composition, and Step C of heat-treating the catalyst precursor composition at a temperature of from 500 to 1100° C. to obtain an electrode catalyst, wherein part or entirety of the transition metal-containing compound includes, as a transition metal element, at least one transition metal element M1 selected from Group IV and Group V elements of the periodic table.

Abstract: A fuel cell electrode catalyst which includes, at least, M1 that is at least one element selected from 3 to 7 group transition metal elements; M2 that is at least one element selected from iron group elements; M3 that is at least one element selected from 13 group elements; carbon; nitrogen; and oxygen, as constitutional elements, wherein when the atomic ratios of the elements (M1:M2:M3:carbon:nitrogen:oxygen) are represented by a:b:c:x:y:z, 0<a<1, 0<b?0.5, 0<c<1, 0<x?6, 0<y?2, 0<z?3 and a+b+c=1, and BET specific surface area is 100 m2/g or more.

Abstract: A method for producing a fuel cell electrode catalyst, including a step (I) of bringing an aqueous solution of a transition metal compound (1) into contact with ammonia and/or ammonia water to generate a precipitate (A) containing an atom of the transition metal, a step (II) of mixing at least the precipitate (A), an organic compound (B), and a liquid medium (C) to obtain a catalyst precursor liquid, and a step (IV) of subjecting the solid in the catalyst precursor liquid to heat treatment at a temperature of 500 to 1200° C. to obtain an electrode catalyst; a portion or the entirety of the transition metal compound (1) being a compound containing a transition metal element of group 4 or group 5 of the periodic table; and the organic compound (B) being at least one selected from sugars and the like.

Abstract: 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.

Abstract: Provided is a process for producing a fuel cell electrode catalyst having high catalytic activity which uses a transition metal, e.g., titanium, which process comprises thermal treatment at relatively low temperature, i.e., not including thermal treatment at high temperature (calcining) step. The process for producing a fuel cell electrode catalyst comprises a step (1) of mixing at least a transition metal-containing compound, a nitrogen-containing organic compound and a solvent to provide a catalyst precursor solution; a step (2) of removing the solvent from the catalyst precursor solution; and a step (3) of thermally treating a solid residue obtained in the step (2) at a temperature of 500 to 1100° C. to provide an electrode catalyst; wherein the transition metal-containing compound is partly or wholly a compound comprising at least one transition metal element (M1) selected from the group 4 and 5 elements of the periodic table as a transition metal element.

Abstract: There is provided an ink for forming a fuel cell catalyst layer that is capable of efficiently forming a high-performance fuel cell catalyst layer inexpensively. The ink for forming a fuel cell catalyst layer of the present invention comprises a fuel cell catalyst, an electron conductive material, a proton conductive material and a solvent, wherein the fuel cell catalyst comprises a metal-containing oxycarbonitride that contains niobium and/or titanium; the mass ratio [(A)/(B)] of the content (A) of the fuel cell catalyst to the content (B) of the electron conductive material is 1 to 6; and the mass ratio [(D)/(C)] of the content (D) of the proton conductive material to the total content (C) of the fuel cell catalyst and the electron conductive material is 0.2 to 0.6.