Cu/CdcO_(3)catalysts for efficient electrochemical CO_(2)reduction over the wide potential window

High efficiency and low-cost catalyst-driven electrocatalytic CO_(2)reduction to CO production are of great significance for energy storage and development.The severe competitive hydrogen evolution reaction occurs at large negative potential window limits the achievement of the target product from CO_(2)at high efficiency.Here,we successfully prepared Cu_(x)/CdcO_(3)composite catalyst rich in interfaces,in which achieved high CO Faraday eficiency exceeded 90%in a wide potential window of 700 mV and highest value up to 97.9%at-0.90V vs.RHE.The excellent performance can be ascribed to the positive contribution of Cu_(x)/CdcO_(3),which maintains a suitable high local pH value during electrochemical reduction,thus inhibiting the competitive hydrogen evolution reaction.Moreover,the compact structure between Cu and CdCO_(3)ensures fast electron transfer both inside catalysts and interface,thus speeding up the reaction kinetics of CO_(2)to CO conversion.Theoretically calculations further prove that the combination of Cu and CdcO_(3)provides the well-defined electronic structure for intermediates adsorption,significantly reducing the reaction barrier for the formation of co.This work provides new insights into the design of eficient electrochemical CO_(2)reduction catalysts for inhibiting hydrogen evolution by adjusting the local pH effect.