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

Abstract

The development of efficient earth-abundant electrocatalysts for N2 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 N2 reduction reaction (NRR) in acid at room temperature and atmospheric pressure in 0.1 M HCl. A rate of NH3 formation of 8.40 × 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.