Electrocatalytic nitrite reduction to ammonia on an Rh single-atom catalyst

Electrocatalytic NO2- reduction to NH3 (NO2RR) holds great promise as a green method for high-efficiency NH3 production. Herein, an Rh single-atom catalyst where isolated Rh supported on defective BN nanosheets (Rh-1/ BN) is reported to exhibit the exceptional NO2RR activity and selectivity. Extensive experimental and theoretical studies unveil that the high NO2RR performance of Rh-1/BN arises from the single-atom Rh sites, which not only promote the activation and hydrogenation of NO2-to-NH3 process, but also hamper the undesired hydrogen evolution. Consequently, Rh-1/BN assembled in a flow cell exhibits the highest NH3 yield rate of 2165.4 mu mol h(-1) cm(-2) and FENH3 of 97.83 % at a high current density of 355.7 mA cm(-2), ranking it the most efficient catalysts for NO2--to-NH3 conversion.