US 12,247,302 B2
Manganese-iridium composite oxide for water splitting catalyst, manganese-iridium composite oxide electrode material, and their production methods
Ryuhei Nakamura, Saitama (JP); Nadege Bonnet, Saitama (JP); Shuang Kong, Saitama (JP); and Kazumasa Suetsugu, Yamaguchi (JP)
Assigned to RIKEN, Saitama (JP); and TOSOH CORPORATION, Yamaguchi (JP)
Appl. No. 17/912,686
Filed by RIKEN, Saitama (JP); and TOSOH CORPORATION, Yamaguchi (JP)
PCT Filed Mar. 19, 2021, PCT No. PCT/JP2021/011501
§ 371(c)(1), (2) Date Sep. 19, 2022,
PCT Pub. No. WO2021/193467, PCT Pub. Date Sep. 30, 2021.
Claims priority of application No. 2020-054589 (JP), filed on Mar. 25, 2020.
Prior Publication US 2023/0175152 A1, Jun. 8, 2023
Int. Cl. C25B 11/075 (2021.01); C01G 55/00 (2006.01); C25B 1/04 (2021.01); C25B 9/23 (2021.01); C25B 11/052 (2021.01); C25B 11/056 (2021.01); C25B 11/063 (2021.01); C25B 11/065 (2021.01); C25D 9/08 (2006.01)
CPC C25B 11/075 (2021.01) [C01G 55/002 (2013.01); C25B 1/04 (2013.01); C25B 9/23 (2021.01); C25B 11/052 (2021.01); C25B 11/056 (2021.01); C25B 11/063 (2021.01); C25B 11/065 (2021.01); C25D 9/08 (2013.01); C01P 2002/52 (2013.01); C01P 2002/72 (2013.01); C01P 2002/77 (2013.01); C01P 2004/03 (2013.01); C01P 2006/40 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A manganese-iridium composite oxide, which has an iridium metal content ratio (iridium/(manganese+iridium)) of 0.1 atomic % or more and 30 atomic % or less, and has interplanar spacings of at least 0.243±0.002 nm, 0.214±0.002 nm, 0.165±0.002 nm and 0.140±0.002 nm.
 
6. An oxygen evolution electrode active material in water electrolysis, containing the manganese-iridium composite oxide as defined in claim 1.
 
11. A method for producing an manganese-iridium composite oxide electrode material comprising an electrically conductive substrate constituted by fibers at least part of which are covered with the manganese-iridium composite oxide as defined in claim 1, which comprises electrodepositing the manganese-iridium composite oxide on the fibers constituting the electrically conductive substrate by electrolysis of a mixed solution containing sulfuric acid/manganese sulfate/iridium salt.
 
12. The method for producing the manganese-iridium composite oxide electrode material according to claim 11, wherein a heat treatment is conducted.
 
14. The production method according to claim 11, wherein the manganese-iridium composite oxide is electrodeposited in a deposition amount of from 0.1 mg/cm2 or more and 25 mg/cm2 or less per geometric area.