Defective Mo2C as a promising electrocatalyst for the nitrogen reduction reaction.

ABSTRACT

The electrocatalytic nitrogen reduction reaction under ambient conditions is considered as a promising alternative to the Haber-Bosch process for NH3 production. However, developing low-cost and high-efficiency electrocatalysts for N2 reduction remains a challenge. Herein, we propose VC-Mo2C with C vacancies as a novel nitrogen reduction reaction (NRR) electrocatalyst based on density functional theory (DFT) calculations. The computational results show that N2 in the gas phase can be fully activated on the surface of VC-Mo2C and can be efficiently reduced to ammonia via a dissociative-associative path with a low limiting potential (-0.43 V). The presence of vacancies enhances the catalytic performance and the collaboration between Mo3 around the vacancies and the remaining substrate d-Mo2C facilitates the overall catalytic reaction. VC-Mo2C also well suppresses the hydrogen evolution reaction (HER) with high selectivity. The present work opens up a new way to promote the sustainable production of NH3.