An Oxygen‐Insensitive Hydrogen Evolution Catalyst Coated by a Molybdenum‐Based Layer for Overall Water Splitting. (13th April 2017)

• Record Type: Journal Article
• Authors: Garcia‐Esparza, Angel T.; Shinagawa, Tatsuya; Ould‐Chikh, Samy; Qureshi, Muhammad; Peng, Xuyuan; Wei, Nini; Anjum, Dalaver H.; Clo, Alain; Weng, Tsu‐Chien; Nordlund, Dennis; Sokaras, Dimosthenis; Kubota, Jun; Domen, Kazunari; Takanabe, Kazuhiro
• Is Part Of: Angewandte Chemie. Volume 129:Number 21(2017)
• Page Start: 5874
• Page End: 5878
• Publication Date: 2017-04-13
• Subjects: Elektrokatalyse -- In-operando-XAS -- Photokatalyse -- Wasserspaltung -- Wasserstoffentwicklung; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201701861
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: For overall water‐splitting systems, it is essential to establish O2 ‐insensitive cathodes that allow cogeneration of H2 and O2 . An acid‐tolerant electrocatalyst is described, which employs a Mo‐coating on a metal surface to achieve selective H2 evolution in the presence of O2 . In operando X‐ray absorption spectroscopy identified reduced Pt covered with an amorphous molybdenum oxyhydroxide hydrate with a local structural order composed of polyanionic trimeric units of molybdenum(IV). The Mo layer likely hinders O2 gas permeation, impeding contact with active Pt. Photocatalytic overall water splitting proceeded using MoO x /Pt/SrTiO3 with inhibited water formation from H2 and O2, which is the prevailing back reaction on the bare Pt/SrTiO3 photocatalyst. The Mo coating was stable in acidic media for multiple hours of overall water splitting by membraneless electrolysis and photocatalysis.