Theoretical screening and investigation on electrocatalytic nitrogen fixation of single transition metal atom supported by monolayer SnS2

Dispersing transition metal atoms on substrates is a novel approach to constructing (photo) electrocatalysts, which has received extensive attention in electrocatalytic nitrogen reduction reaction (NRR). Two-dimensional monolayer SnS2 is an easy-to-prepare, low-cost, and low-environmental pollution material. In this work, through first-principles calculation, fifteen transition metal atoms (TM = Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zr, Mo, Ru, Hf, Ta, W, Os) supported on monolayer SnS2 (TM@SnS2), respectively, are investigated as an efficient NRR catalyst. The screening of the NRR catalyst is followed by a three-step method and our results indicate that a single W atom supported on top of the Sn atom of SnS2 (W@SnS2) has the best catalytic activity, with an over potential of 0.42 V along the distal pathway, which is much lower than the reported values based on SnS2. Moreover, the N2 adsorption on W@SnS2 is far superior to the hydrogen atom adsorption, which can inhibit the competitive side reaction effectively. Our results are helpful for the design of NRR catalysts based on SnS2 monolayer.