Molybdenum disulfide (MoS2)-based electrocatalysts for hydrogen evolution reaction: From mechanism to manipulation

Molybdenum disulfide (MoS2)-based materials as the non-noble metal catalysts have displayed the potential capability to drive electrocatalytic hydrogen evolution reaction (HER) for green hydrogen production along with their intrinsic activity, tunable electronic properties, low cost, and abundance reserves, which have attracted intensive attention as alternatives to the low-abundance and high-cost platinum-based catalysts. However, their insufficient catalytic HER activities and stability are the major challenges for them to become practically applicable. Hereby, the MoS2-based electrocatalysts for HER are comprehensively reviewed to explain the fundamental science behind the manipulations of the crystal structure, microstructure, surface, and interface of MoS2 in order to enhance its catalytic performance through changing the electrical conductivity, the number of active sites, surface wettability, and the Gibbs free energy for hydrogen adsorption (ΔGH). Recent studies in surface/interface engineering, such as phase engineering, defect engineering, morphology design, and heterostructure construction, are analyzed to reveal the state-of-the-art strategies for designing and preparing the cost-effective and high-performance MoS2-based catalysts through optimizing the charge transfer, surface-active sites, ΔGH, and surface hydrophilicity. Lastly, the perspectives, challenges, and future research directions of HER electrocatalysis are also given to facilitate the further research and development of HER catalysts.