writer：Zhao, XW (Zhao, Xiwang) [1] ; Bao, JH (Bao, Jiehua) [1] , [2] ; Zhou, YM (Zhou, Yuming) [1] ; Zhang,
keywords：ACTIVE EDGE SITESEFFICIENTOPTIMIZATIONTRANSITIONCATALYSTSOXYGENMO
source：期刊
Issue time：2022年
Currently, two-dimensional (2D) layered transition metal chalcogenides (TMCs), especially MoS2, are attracting widespread attention in the field of water electrolysis. Unfortunately, the catalytic activity of MoS2 is limited to a few edge sites and by its low conductivity. Herein, MoS2/NiS heterostructures possessing a flower-like morphology were constructed via an accurate thermal treatment process to realize precise interface modification. As expected, through the adjunction of a certain amount of polyvinylpyrrolidone, NiS grew uniformly on the surface of MoS2 nanosheets, thereby forming a large number of visual lattice fringes with a specific interplanar spacing, which promoted a higher electron-transfer efficiency. The better electron-transfer efficiency resulted in a better hydrogen evolution reaction performance, providing an overpotential of 158 mV at 10 mA cm(-1), a Tafel slope of 128.1 mV dec(-1), and significantly long-term durability. Moreover, density functional theory calculation also showed that the precise interface modification of MoS2/NiS heterostructure exhibited more occupations at the Fermi level, which improved the electrical conductivity. Additionally, the MoS2/NiS catalysts achieved a moderately lower hydrogen adsorption energy (Delta G(H*)), indicating that it had better catalytic hydrogen evolution performance. This work can be extended to design other catalytic materials and for understanding reactions in the fields of energy conversion through theoretical calculations.