High-Efficiency Electrosynthesis of Ammonia with High Selectivity under Ambient Conditions Enabled by VN Nanosheet Array

The development of efficient earth-abundant electrocatalysts for N-2 reduction to ammonia (NH3) under ambient conditions is critical for achieving a low-carbon and sustainable-energy society. Herein, we report the development of VN nanosheet array on Ti mesh as an active and selective electrocatalyst for N-2 reduction reaction (NRR) in acid at room temperature and atmospheric pressure in 0.1 M HCl. A rate of NH3 formation of 8.40 x 10(-11) mol s(-1) cm(-2) is obtained at -0.50 V with a Faradaic efficiency of 2.25%. Notably, such catalyst material also exhibits high selectivity (no formation of N2H4) and electrochemical stability. Theoretical and experiment results suggest that VN catalyzes NRR via a Mars-van Krevelen mechanism. This study would offers the potential of utilization of attractive 3D catalyst electrode toward efficient NH3 synthesis for applications.