Electrocatalytic nitrite reduction to ammonia on isolated bismuth alloyed ruthenium

Electrochemical reduction of NO2- to NH3（NO2-RR） is recognized as an appealing approach for achieving renewable NH3 synthesis and waste NO2- removal.Herein,we report isolated Bi alloyed Ru （Bi1Ru） as an efficient NO2-RR catalyst.Theoretical calculations and in situ electrochemical measurements reveal the creation of Bi1-Ru dual sites which can remarkably promote NO2- activation and suppress proton adsorption,while accelerating the NO2-RR protonation energetics to render a high NO2--to-NH3conversion efficiency.Remarkably,Bi1Ru assembled in a flow cell delivers an NH3 yield rate of 1901.4μmol h-1cm-2and an NH3-Faradaic efficiency of 94.3%at an industrial-level current density of 324.3 mA cm-2.This study offers new perspectives for designing and constructing p-block single-atom alloys as robust and high-current-density NO2-RR catalysts toward the ammonia electrosynthesis.