Single‐Atom Bi Alloyed Pd Metallene for Nitrate Electroreduction to Ammonia

Abstract

AbstractElectrochemical reduction of nitrate to ammonia (NO3RR) holds a great promise for attaining both NH3electrosynthesis and wastewater purification. Herein, single‐atom Bi alloyed Pd metallene (Bi1Pd) is reported as a highly effective NO3RR catalyst, showing a near 100% NH3‐Faradaic efficiency with the corresponding NH3yield of 33.8 mg h−1 cm−2at −0.6 V versus RHE, surpassing those of almost all ever reported NO3RR catalysts. In‐depth theoretical and operando spectroscopic investigations unveil that single‐atom Bi electronically couples with its neighboring Pd atoms to synergistically activate NO3−and destabilize *NO on Bi1Pd, leading to the reduced energy barrier of the potential‐determining step (*NO→*NOH) and enhanced protonation energetics of NO3−‐to‐NH3pathway.