Single transition metal atom anchored on VSe2 as electrocatalyst for nitrogen reduction reaction

There has been an increasing interest in converting nitrogen (N2) to ammonia (NH3) via electrochemical nitrogen reduction reaction (NRR). In this study, the NRR catalytic performance of a series of single transition metal (TM) atoms anchored on two dimensional VSe2 (TM-VSe2) was studied via performing the first-principles calculations. Among the investigated single-atom catalyst of TM-VSe2, W-VSe2 demonstrates the best NRR catalytic performance with a limiting potential of −0.36 V and effective inhibition of the competitive hydrogen evolution reaction. Meanwhile, our calculations demonstrate that W-VSe2 is highly stable as single-atom anchored on the surface of VSe2 monolayer, whose improved electrical conductivity ensures the electron transform during NRR process. Moreover, we found that the limiting potential of NRR on TM-VSe2 was negatively correlated with the adsorption energy of reaction intermediate *N-NH, and related with the total magnetic moment of TM-VSe2. Importantly, we identified the origin of the NRR catalytic activity from electronic aspect. Our results provide a new way for measuring the NRR catalytic activity of single-atom catalysts.