Importance of Nickel Oxide Lattice Defects for Efficient Oxygen Evolution Reaction

• DOI: 10.1021/acs.chemmater.1c02406
• Publication Date: 2021-10-21T10:12:01Z
• Authors: Hannes Radinger; Paula Connor; Sven Tengeler; Robert W. Stark; Wolfram Jaegermann; Bernhard Kaiser
• Keywords: Nickel oxide; Oxygen evolution

Nickel oxide/hydroxides [NiOx(OH)y] are considered to be promising materials replace noble metals for the oxygen evolution reaction in alkaline media. While several studies showed that iron impurities promote activity of nickel-based catalysts, effects intrinsic nickel defects and underlying mechanism remain unknown. In this work, X-ray photoelectron spectroscopy is combined with surface-enhanced Raman scattering understand reactivity NiOx thin films, which were prepared at different temperatures thus varied their chemical composition crystalline order. was used follow characteristic oxidation species from NiII(OH)2 NiIIIOOH NiIVOO– under electrochemical conditions. A stronger oxide-to-hydroxide conversion, consistent post-electrochemistry study, associated presence initial NiIII vacancies appears beneficial electrocatalytic activity.