Density Functional Theory Study on the Hydrogen Evolution Reaction in the S-rich SnS2 Nanosheets

In this work, the effect of S-rich condition on the catalytic activity of the hydrogen evolution reaction in monolayer SnS 2 edges was investigated using density functional theory. The results showed that the catalytic active sites for hydrogen evolution reaction (HER) in stoichiometry SnS 2 monolayer locate at the (100) edge site, whereas the basal plane and (010) edge are inert for HER. The S-rich (100) and (010) edges are all catalytic active for HER with a large range of hydrogen coverage. Projected density of state analysis revealed that the mechanism for the improvement of catalytic activity is due to formation of density of states near the Fermi energy level by the S 2 and S 3 terminations. This work provides a new design methodology to improve the catalytic activity of catalysts based on transition metal dichalcogenides. Graphical Abstract