A First Principle Study to Understand the Importance of Edge‐exposed and Basal Plane Defective MoS2 Towards Nitrogen Reduction Reaction

Nitrogen reduction reaction (NRR) as a promising approach to ammonia synthesis has received much attention in recent years. Herein, by using density functional theory (DFT) calculations, we constructed edge‐exposed MoS2 and different kinds of basal plane defects, including anti‐site, sulfur vacancy and pore defects, to systematically investigate their influence on the NRR performance. The thermodynamically calculated results revealed that the NRR on edge‐exposed MoS2, anti‐site defects, sulfur vacancy with three sulfur atoms missing (S3V) and porous defect (D) exhibit great catalytic activity with low limiting potentials. The calculated limiting potentials are ‐0.43 and ‐0.47 V at armchair and zigzag edge MoS2, ‐0.42 and ‐0.44 V at anti‐site defects, ‐0.49 and ‐0.67 V at S3V and D. However, by inspecting the thermodynamic properties of the hydrogen evolution reaction, we proposed that the zigzag‐end MoS2 and anti‐site defects exhibit a better NRR selectivity compared to armchair‐end MoS2, S3V and D. Electronic structure calculations reveals that the edge‐exposed and basal plane defective MoS2 can improve the conductivity of the material by reducing the band gap. Donation‐backdonation mechanism can effectively promote the activation of nitrogen molecule.