Defective Carbon-Doped Boron Nitride Nanosheets for Highly Efficient Electrocatalytic Conversion of N2 to NH3

In industry, ammonia (NH3) is currently produced by Haber-Bosch technology, which suffers from the drawbacks of high energy consumption and CO2 emission. Artificial N-2 fixation in aqueous solution under ambient conditions has been recently pushed forward by developing electrocatalysts with high efficiency and high selectivity for NH3 production. Herein, we demonstrate that defective carbon-doped boron nitride nanosheets (C-BN) show excellent electrocatalytic activity and durability in N-2 fixation. To be used as a cathode catalyst, C-BN achieves an NH3 production rate of 36.7 mu g h(-1) mg(cat)(-1) at -0.55 V vs a reversible hydrogen electrode (RHE), which is much higher than that of the synthesized and exfoliated boron nitride nanosheets. The faradic efficiency of C-BN attains 6.51% at -0.55 V vs RHE, which indicates excellent selectivity of the N-2 reduction reaction (NRR). Furthermore, the catalysts show great stability during electrolysis and recycling tests. In principle, carbon doping and the defective structure contribute to the promoted NRR performance of C-BN.