Recent strategies for improving the catalytic activity of ultrathin transition metal sulfide nanosheets toward the oxygen evolution reaction

Hydrogen is considered as one of the clean secondary energy sources required in industry and daily life. Electrocatalytic hydrogen production is believed to be the most reliable method for converting renewable energy into chemical energy. Two-dimensional (2D) transition metal disulfides (TMDs), as an emerging electrocatalysts, have been widely investigated for oxygen evolution reaction (OER) in water splitting. Herein, this review summarizes the recent progress and the strategies of ultrathin TMDs for improving the OER electrocatalytic activities. The basic catalytic mechanism of OER is first introduced, and then the catalytic characteristics of 2D TMDs are presented. Importantly, this review specifically concentrates on strategies to improve catalytic activity such as phase engineering, defect/vacancy engineering, heterostructure, doping effect, and catalyst support material. It can be concluded that these regulatory strategies can largely enhance the electrocatalytic performance by increasing the active site exposure and improving the electrocatalytic kinetics. In addition, the challenges and perspectives of 2D TMDs catalysts are presented, which offers valuable guidance in designing efficient and low-cost OER electrocatalysts for future energy applications. We hope that this review will inspire future studies and bridge the gap between strategy design and practical application.