Strategies to improve electrocatalytic and photocatalytic performance of two-dimensional materials for hydrogen evolution reaction

Two-dimensional materials (2D) with unique physicochemical properties have been widely studied for their use in many applications, including as hydrogen evolution catalysts to improve the efficiency of water splitting. Recently, typical 2D materials MoS2, graphene, MXenes, and black phosphorus have been widely investigated for their application in the hydrogen evolution reaction (HER). In this review, we summarize three efficient strategies—defect engineering, heterostructure formation, and heteroatom doping—for improving the HER performance of 2D catalysts. The d-band theory, density of states, and Fermi energy level are discussed to provide guidance for the design and construction of novel 2D materials. The challenges and prospects of 2D materials in the HER are also considered.