Generating Defect-Rich Bismuth for Enhancing the Rate of Nitrogen Electroreduction to Ammonia

The electrochemical N-2 fixation, which is far from practical application in aqueous solution under ambient conditions, is extremely challenging and requires a rational design of electrocatalytic centers. We observed that bismuth (Bi) might be a promising candidate for this task because of its weak binding with H adatoms, which increases the selectivity and production rate. Furthermore, we successfully synthesized defect-rich Bi nanoplates as an efficient noble-metal-free N-2 reduction electrocatalyst via a low-temperature plasma bombardment approach. When exclusively using (HNMR)-H-1 measurements with N-2 gas as a quantitative testing method, the defect-rich Bi(110) nanoplates achieved a (NH3)-N-15 production rate of 5.453 mu gmg(Bi)(-1)h(-1) and a Faradaic efficiency of 11.68% at -0.6V vs. RHE in aqueous solution at ambient conditions.