Electroreduction of CO2 and nitrate for urea synthesis on a low-coordinated copper catalyst

Abstract

Electroreduction of CO₂ and NO₃⁻ to urea (ECNU) offers a fascinating route for migrating NO₃⁻ pollutants and synthesizing valuable urea. Herein, low-coordinated copper (L-Cu) is developed as an effective ECNU catalyst, delivering the highest urea yield rate of 30.96 mmol h⁻¹ g⁻¹ and urea-faradaic efficiency of 50.42% in a flow cell. Theoretical calculations reveal that Cu sites and low-coordinated Cu (Cu_L) sites on L-Cu can synergistically promote C–N coupling and inhibit the competing side reactions, leading to a high CO₂/NO₃⁻-to-urea efficiency.