A Computational Study of Strained MoS2 as Catalysts for the Electrocatalytic Nitrogen Reduction Reaction

• The catalytic activity of the strained MoS 2 catalyst is studied. • The N 2 H formation and NH 3 desorption are important steps in the NRR process. • The S vacancy is the active center and the stress can improve catalytic activity. • The strained MoS 2 with a stress increase of 4% is the highest catalytic activity. • The stress conditions can inhibit the HER. Electrocatalytic nitrogen reduction reaction (NRR) is a green and sustainable method for ammonia (NH 3 ) synthesis, and electrocatalytic NRR may be a potential substitute for the industrial Haber–Bosch NH 3 synthesis process. However, it is very necessary to develop efficient and low-cost NRR electrocatalysts because of the poor catalytic activity, strong competitiveness of the hydrogen evolution reaction (HER), and low yield of NH 3 for the currently reported NRR electrocatalysts. In this study, using the first-principles computational simulation, the catalytic activity of the MoS 2 catalyst, combining S defect and stress, for the NRR is systematically studied. The N 2 H formation and NH 3 desorption are very important steps in the NRR process. Through screening, it is indicated that S vacancy is the active center, and the stress can improve the catalytic activity. Further, it is preliminarily judged that the strained MoS 2 with a stress increase of 4% can effectively promote N 2 H formation and NH 3 desorption; it is superior to the catalysts under other stress conditions, and it can considerably inhibit the HER. Our results provide an important theoretical basis for the application of the strained MoS 2 catalyst in the field of the NRR and provide a reasonable design principle for the further discovery of high-performance catalysts.