Operando Identification of the Reversible Skin Layer on Co₃O₄ as a Three-Dimensional Reaction Zone for Oxygen Evolution.

ABSTRACT: Co oxides and oxyhydroxides have been studied extensively in the past as promising electrocatalysts for the oxygen evolution reaction (OER) in neutral to alkaline media. Earlier studies showed the formation of an ultrathin CoO _x (OH) _y skin layer on Co₃O₄ at potentials above 1.15 V vs reversible hydrogen electrode (RHE), but the precise influence of this skin layer on the OER reactivity is still under debate. We present here a systematic study of epitaxial spinel-type Co₃O₄ films with defined (111) orientation, prepared on different substrates by electrodeposition or physical vapor deposition. The OER overpotential of these samples may vary up to 120 mV, corresponding to two orders of magnitude differences in c

SUBMITTER: Wiegmann T 

PROVIDER: S-EPMC8939430 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature