Research progress of MoS2-based electrode materials in electrocatalytic hydrogen evolution: from synthesis, characterization to electrocatalytic performance optimization strategy

Electrocatalytic water splitting is a promising approach for producing hydrogen, with the development of efficient and stable catalysts playing a critical role in its industrialization process. Molybdenum disulfide (MoS2) has emerged as a promising catalyst due to its edge active sites and a variety of different phase structures. However, the inert basal plane and unsatisfactory electrical conductivity of MoS2 still have a certain gap with platinum (Pt) family catalysts. Numerous optimization strategies have been developed to enhance the hydrogen evolution reaction (HER) performance of MoS2. In this review, we first provide an overview of the synthesis and characterization methods of MoS2. Then, the important work of optimizing the HER performance of MoS2 was summarized from six aspects: structural engineering, defect engineering, strain engineering, phase engineering, doping engineering, and heterojunction engineering. The work of optimizing MoS2 for current metal single atoms (SAs) is divided into single-atom doping and single-atom loading to better understand the enhancement mechanism of its HER activity. Furthermore, the in-situ characterization and theoretical calculation of MoS2-based electrocatalysts were described and summarized to explore its intrinsic active site during HER. Finally, we delve into the challenges encountered by MoS2-based catalysts in terms of industrialization and explore potential future research directions. This review will help researchers understand and develop MoS2-based catalysts.