Atomically dispersed Pd on defective BN nanosheets for nitrite electroreduction to ammonia

Electrocatalytic NO2- reduction to NH3 (NO2RR) offers a prospective strategy to concurrently achieve polluted NO2- removal and effective NH3 electrosynthesis. In this work, we report atomically dispersed Pd on defective BN nanosheets (Pd-1/BN) as an efficient catalyst for the NO2RR, achieving the highest NH3-Faradaic efficiency of 91.7% with an NH3 yield rate of 347.1 mu mol h(-1) cm(-2) at -0.6 V vs. RHE, superior to those of most previously reported electrocatalysts. Theoretical computations reveal the isolated Pd sites as catalytic centers to selectively adsorb NO2- and accelerate NO2- -to-NH3 hydrogenation process with a minimized reaction barrier, eventually contributing to the considerably enhanced NO2RR selectivity and activity of Pd-1/BN.