Rapid Surface Reconstruction of Amorphous Co(OH)<sub>2</sub>/WO<sub><i>x</i></sub> with Rich Oxygen Vacancies to Promote Oxygen Evolution
Sijun Li, Hua Wang, Zemian Ma, Qinglan Xiao, Qin Gao, Yimin Jiang, Wei Shen, Rongxing He, Ming Li
Abstract
Abstract Herein, a transition metal dissolution‐oxygen vacancy strategy, based on dissolution of highly oxidized transition metal species in alkaline electrolyte, was suggested to construct a high‐performance amorphous Co(OH) 2 /WO x (a‐CoW) catalyst for the oxygen evolution reaction (OER). The surface reconstruction of a‐CoW and its evolution were described by regulating oxygen vacancies. With continuous dissolution of W species, oxygen vacancies on the surface were generated rapidly, the surface reconstruction was promoted, and the OER performance was improved significantly. During the surface reconstruction, W species also played a role in electronic modulation for Co. Due to its rapid surface reconstruction, a‐CoW exhibited excellent OER performance in alkaline electrolyte with an overpotential of 208 mV at 10 mA cm −2 and had long‐term stability for at least 120 h. This work shows that the transition metal dissolution‐oxygen vacancy strategy is effective for preparation of high‐performance catalysts.