Zhao, WanghuiZhang, LifuLuo, QiquanHu, ZhenpengZhang, WenhuaSmith, SeanYang, Jinlong2020-05-262155-5435http://hdl.handle.net/1885/204675Searching for new types of electrocatalysts with high stability, activity, and selectivity is essential for the production of ammonia via electroreduction of nitrogen. Using density functional theory (DFT) calculations, we explore the stability of single metal atoms (M1) supported on nitrogen-doped graphene (N3-G); the competitive adsorption of dinitrogen and hydrogen; and the potential competition of first dinitrogen protonation and hydrogen adsorption on metal sites. Consequently, we identify Mo1/N3-G and Cr1/N3-G as candidate electrocatalysts for nitrogen reduction reaction (NRR). The theoretically predicted selectivities (overpotentials) are 40% (0.34 V) and 100% (0.59 V) on Mo1/N3-G and Cr1/N3-G, respectively. The electroreduction of nitrogen proceeds via distal-to-alternating hybrid mechanism with two spectator dinitrogen molecules. The high stability, high selectivity to ammonia, and relatively low overpotentials for NRR suggest Mo1(Cr1)/N3-G as the most promising electrocatalyst among those studied for electroreduction of nitrogen.This work was supported by the National Key Research and Development Program (Grant Nos. 2018YFA0208600, 2016YFA0200600), the National Natural Science Foundation of China (21473167, 21688102, 21703222), the Fundamental Research Funds for the Central Universities (WK3430000005) and partially by the support of China Scholarship Council (CSC) (File No. 201706345015). The calculations were performed on the supercomputing system in USTC-SCC and Guangzhou-SCC.application/pdfen-AU© 2019 American Chemical Society201910.1021/acscatal.8b050612019-12-19