Platinum Nanocrystals Decorated on Defect-Rich MoS2 Nanosheets for pH-Universal Hydrogen Evolution Reaction

Hydrogen evolution reaction (HER) has drawn substantial attention owing to its crucial role in clean energy production via water electrolysis. Developing highly efficient and electrochemically stable HER catalysts that can work under a wide range of pH values is of great importance. Herein, uniformly distributed platinum nanocrystals were decorated on defect-rich MoS2 nanosheets (DR-MoS2) via an in situ electrochemical dissolution-redeposition approach. With the merits of the defect-rich feature combined with the large surface area of the DR-MoS2, abundant reactive sites can be provided for adsorbing and anchoring the Pt atoms, leading to the formation of the DR-MoS2 catalyst with homogeneous decorated Pt nanocrystals. Benefitting from the synergistic effect between the DR-MoS2 and the Pt nanocrystals, the DR-MoS2-Pt composite catalyst shows remarkable HER performance in acidic and alkaline conditions, even taking precedence over the benchmarking Pt/C catalyst.