# US 2014/0193739 A1 · Oxygen reduction catalyst, method for producing the same, and polymer electrolyte fuel cell > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0193739 A1 - Document ID: US20140193739A1 - Status: Published application - Kind: A1 - Application number: 14/232,409 - Filed: 2012-04-13 - Published: 2014-07-10 - Earliest claimed: 2011-07-14 - Assignees: Showa Denko K.K. - Inventors: Akira Takahashi; Takuya Imai; Ryuji Monden; Yasuaki Wakizaka; Takashi Sato - Web page: https://patentgrep.com/patent/US20140193739A1 ## CPC - H01M 4/8652: {as mixture} - H01M 4/9016: {Oxides, hydroxides or oxygenated metallic salts} - H01M 4/9091: {Unsupported catalytic particles; loose particulate catalytic materials, e.g. in fluidised state} - H01M 2004/8689: {Positive electrodes} - H01M 2008/1095: {Fuel cells with polymeric electrolytes} - Y02E 60/50: Fuel cells - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract It is an object of the present invention to provide an oxygen reducing catalyst having high catalytic activity and high durability using a transition metal (such as titanium); and a method for producing a fuel cell electrode catalyst using the oxygen reducing catalyst. The present invention provides the oxygen reduction catalyst including titanium, carbon, nitrogen, and oxygen as constituent elements at a specific ratio, wherein in XRD measurement using a Cu—Kα ray, peaks are each present in at least regions A and B among regions A to D which occupy 2θ ranges of 42° to 43°, B: 36.5° to 37°, 25° to 26°, and 27° to 28°, respectively; and each of maximum peak intensities IA, IB, IC, and ID in the regions A to D satisfies both relationships of IA>IB and 0.3≦(IA/(IA+IC+ID))≦1. ## Claims ### Claim 1 An oxygen reduction catalyst comprising titanium, carbon, nitrogen, and oxygen as constituent elements, wherein 0.1IB (1), and 0.3≦(IA/(IA+IC+ID))≦1 (2). ### Claim 2 (depends on 1) The oxygen reduction catalyst according to claim 1, further comprising at least one transition metal element M2 selected from iron, nickel, chromium, cobalt, vanadium, and manganese. ### Claim 3 (depends on 1) A method for producing the oxygen reduction catalyst according to claim 1, the method comprising steps 1 to 3 described below: step 1: the step of mixing at least a titanium-containing compound (1a), a nitrogen-containing organic compound (2), and a solvent to give a catalyst precursor solution; step 2: the step of removing the solvent from the catalyst precursor solution to give a solid residue; and step 3: the step of heat-treating the solid residue, obtained in the step 2, at a temperature of 900° C. to 1400° C. to give the oxygen reduction catalyst, wherein any of the components to be mixed comprises an oxygen atom. ### Claim 4 (depends on 3) The method according to claim 3, wherein in the step 1, a compound (1b) containing at least one transition metal element M2 selected from iron, nickel, chromium, cobalt, vanadium, and manganese is further added. ### Claim 5 (depends on 3) The method according to claim 3, wherein in the step 1, a compound (3) containing at least one element selected from the group consisting of boron, phosphorus, and sulfur as well as fluorine is further added. ### Claim 6 (depends on 5) The method according to claim 5, wherein the compound (3) is at least one selected from the group consisting of boric acid derivatives containing fluorine, sulfonic acid derivatives containing fluorine, and phosphoric acid derivatives containing fluorine. ### Claim 7 (depends on 3) The method according to claim 3, wherein the solvent comprises alcohol or water. ### Claim 8 (depends on 3) The method according to claim 3, wherein the titanium-containing compound (1a) is one or more selected from the group consisting of titanium complexes as well as phosphates, sulfates, nitrates, organic acid salts, oxyhalides, alkoxides, halides, perhalates, and hypohalites of titanium. ### Claim 9 (depends on 3) The method according to claim 3, wherein the nitrogen-containing organic compound (2) has, in its molecule, one or more selected from amino group, nitrile group, imido group, imine group, nitro group, amide group, azido group, aziridine group, azo group, isocyanate group, isothiocyanate group, oxime group, diazo group, nitroso group, pyrrole ring, porphyrin ring, imidazole ring, pyridine ring, pyrimidine ring, and pyrazine ring. ### Claim 10 (depends on 3) The method according to claim 3, wherein the nitrogen-containing organic compound (2) has, in its molecule, one or more selected from hydroxyl group, carboxyl group, formyl group, halocarbonyl group, sulfonate group, phosphate group, ketone group, ether group, and ester group. ### Claim 11 (depends on 3) The method according to claim 3, wherein in the step 3, the solid residue is heat-treated in a non-oxidizing atmosphere. ### Claim 12 (depends on 11) The method according to claim 11, wherein the non-oxidizing atmosphere is an atmosphere containing nitrogen. ### Claim 13 (depends on 11) The method according to claim 11, wherein the non-oxidizing atmosphere is an atmosphere containing 1% by volume or more and 20% by volume or less of a hydrogen gas. ### Claim 14 (depends on 3) An oxygen reduction catalyst produced by the method according to claim 3. ### Claim 15 (depends on 1) A fuel cell electrode catalyst comprising the oxygen reduction catalyst according to claim 1. ### Claim 16 (depends on 1) An ink comprising the oxygen reduction catalyst according to claim 1. ### Claim 17 (depends on 16) A fuel cell catalyst layer produced using the ink according to claim 16. ### Claim 18 (depends on 17) An electrode comprising the fuel cell catalyst layer according to claim 17 and a gas diffusion layer. ### Claim 19 (depends on 17) A membrane electrode assembly comprising: an anode; a cathode comprising the fuel cell catalyst layer according to claim 17; and an electrolyte membrane between the anode and the cathode. ### Claim 20 (depends on 19) A polymer electrolyte fuel cell comprising the membrane electrode assembly according to claim 19.