Theoretical Study on V Atom Supported on N and P-Doped Defective Graphene for Electrocatalytic Nitrogen Reduction
Wei Song, Ran Wang, Xiao Liu, Yongliang Guo, Ling Fu, Chaozheng He
Abstract
Ammonia (NH 3 ) is one of the most extensively produced chemicals worldwide, and it plays an important and indispensable role in the global economy. At present NH 3 is mainly produced by the traditional Haber-Bosch process operated at high pressure and temperature, which results in massive energy consumption and carbon dioxide emissions. The electrochemical nitrogen reduction reaction (NRR) can allow the production of NH 3 from nitrogen and water under ambient conditions and is regarded as a sustainable alternative to the Haber–Bosch process because of its low energy consumption and limited environmental impact. In this study, using density functional theory calculations, we designed a monovacancy defective graphene (MVG) doped with various nitrogen and phosphorus atoms and a single vanadium atom (VN 1–3 @MVG and VP 1–3 @MVG) to be used as electrocatalysts. The results revealed that N- and P-doping are beneficial for N 2 adsorption and activation and can effectively reduce the energy barrier of the NRR, especially for P-doping. Among the synthesized electrocatalysts, double P-doped V@MVG demonstrated the best catalytic activity with a low free energy barrier of 0.43 eV. This paper reports the development of an efficient catalyst for electrochemical NH 3 synthesis and provides valuable insights on the design of electrocatalysts with high activity and stability.