Theoretical screening of group IIIA-VIIA elements doping to promote hydrogen evolution of MoS2 basal plane

Abstract

MoS2, as a low-cost catalyst for hydrogen evolution reaction (HER), suffers from poor catalytic performance on the basal plane. Herein, by doping 19 main-group elements on the S-defective MoS2 nanosheet, the most promising MoS2-based catalysts for the HER are screened with high-throughput density functional theory (DFT) calculations. Remarkably, the doping of main-group elements except chalcogens can improve the activity of the MoS2 basal plane to a certain extent. The S-defective MoS2 monolayer doped with In/Ge atom (In3@MoS2 and Ge3@MoS2) show excellent HER performance, and their reaction barrier is even lower than that of commercial Pt/C catalyst. In In3@MoS2 and Ge3@MoS2, the In/Ge atoms act as electron donors to increase the unoccupied anti-bonding orbital, which enhances the interaction of In/Ge-H bonding. On the other hand, the unique co-existence of electron-depletion and electron-accumulation regions near In/Ge atoms enables the adsorption of free radical H to be moderate. Moreover, the In/Ge atoms also increase the conductivity of MoS2, especially the In atom brings a new impurity state near the Fermi level. This work presents a promising strategy for exploiting high-performance MoS2-based catalysts for HER, and would stimulate more researchers to optimize other two-dimensional materials by doping main-group elements for HER.