Catalyst

Patent metadata

Field	Value
Publication number	US-2017244109-A1
Application number	US-201515509660-A
Country	US
Kind code	A1
Filing date	Sep 8, 2015
Priority date	Sep 8, 2014
Publication date	Aug 24, 2017
Grant date	—

Abstract

A catalyst comprising particles of iridium oxide and a metal oxide (M oxide), wherein the metal oxide is selected from the group consisting of a Group 4 metal oxide, a Group 5 metal oxide, a Group 7 metal oxide and antimony oxide, wherein the catalyst is prepared by subjecting a precursor mixture to flame spray pyrolysis, wherein the precursor mixture comprises a solvent, an iridium oxide precursor and a metal oxide precursor is disclosed. The catalyst has particular use in catalysing the oxygen evolution reaction.

First claim

1 . A catalyst comprising particles of iridium oxide and a metal oxide (M oxide), wherein the metal oxide is selected from the group consisting of a Group 4 metal oxide, a Group 5 metal oxide, a Group 7 metal oxide and antimony oxide, wherein the catalyst is prepared by subjecting a precursor mixture to flame spray pyrolysis, wherein the precursor mixture comprises a solvent, an iridium oxide precursor and a metal oxide precursor, wherein the surface area of the catalyst is ≧50 m2/g.

2 . A catalyst according to claim 1 , wherein the metal oxide is selected from the group consisting of tantalum oxide, titanium oxide, antimony oxide, manganese oxide and niobium oxide.

3 . A catalyst according to claim 1 , wherein the atomic ratio of iridium to metal in the metal oxide is from 80:20 to 40:60.

4 . A catalyst comprising particles of iridium oxide and a metal oxide, characterised in that the surface area of the catalyst is ≧50 m2/g and the particles of iridium oxide and the metal oxide have a d90≦15 nm.

5 . A process for preparing a catalyst comprising particles of iridium oxide and a metal oxide, wherein the metal oxide is selected from the group consisting of a Group 4 metal oxide, a Group 5 metal oxide, a Group 7 metal oxide and antimony oxide, said process comprising subjecting a precursor mixture to flame spray pyrolysis, wherein the precursor mixture comprises a solvent, an iridium oxide precursor and a metal oxide precursor, wherein the surface area of the catalyst is ≧50 m2/g.

6 . A process according to claim 5 , wherein said process further comprises an annealing step.

7 . A catalyst layer comprising a catalyst according to claim 1 and an electrocatalyst.

8 . A gas diffusion electrode comprising a gas diffusion layer and a catalyst layer according to claim 7 .

9 . A catalysed membrane comprising an ion-conducting membrane and a catalyst layer according to claim 7 .

10 . A catalysed carrier/transfer substrate comprising a carrier/transfer substrate and a catalyst layer according to claim 7 .

11 . A membrane electrode assembly comprising a catalyst according to claim 1 .

12 . An electrochemical device, comprising a catalyst according to claim 1 .

13 . (canceled)

14 . (canceled)

15 . (canceled)

16 . A catalyst according to claim 2 , wherein the atomic ratio of iridium to metal in the metal oxide is from 80:20 to 40:60.

17 . A catalyst layer comprising a catalyst according to claim 4 and an electrocatalyst.

18 . A gas diffusion electrode comprising a gas diffusion layer and a catalyst layer according to claim 17 .

19 . A catalysed membrane comprising an ion-conducting membrane and a catalyst layer according to claim 17 .

20 . A catalysed carrier/transfer substrate comprising a carrier/transfer substrate and a catalyst layer according to claim 17 .

21 . A membrane electrode assembly comprising a catalyst according to claim 4 .

22 . A membrane electrode comprising a catalyst layer according to claim 7 .

23 . A membrane electrode comprising a catalyst layer according to claim 17 .

24 . A membrane electrode assembly comprising a gas diffusion electrode according to claim 8 .

25 . A membrane electrode assembly comprising a gas diffusion electrode according to claim 18 .

26 . A membrane electrode assembly comprising a catalysed membrane according to claim 9 .

27 . A membrane electrode assembly comprising a catalysed membrane according to claim 19 .

28 . An electrochemical device comprising a catalyst according to claim 4 .

Assignees

• Johnson Matthey Fuel Cells Ltd

Inventors

• O'Malley Rachel Louise
• Petrucco Enrico
• Johnson Simon

Classifications

• B01J23/64

  with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium · CPC title

• B01J31/04

  containing carboxylic acids or their salts {(B01J31/0277 - B01J31/0298 take precedence; multi-metal carboxylate complexes like Pd (II) acetate, i.e. Pd3 (OAc) 6 or Cr(II)acetate, i.e. Cr2(OAc)4 B01J31/2226)} · CPC title

• B01J23/468

  Iridium · CPC title

• H01M4/8652

  as mixture · CPC title

• B01J37/349

  making use of flames, plasmas or lasers · CPC title