Zn-Bi bimetallic catalyst for electrochemical synthesis of C1 products by highly selective CO2 reduction

Abstract

Electrochemical reduction of CO2 into valuable chemicals is an effective way to achieve carbon neutrality. Here, we report a method to synthesize a Zn-Bi bimetallic catalyst (Zn-Bi2O3/CN) with excellent performance in electrochemical CO2 reduction reaction (ECO2RR), consisting of Bi2O3/CN decorated with Zn. Particularly, the Zn-Bi2O3/CN could achieve high FEC1 (FEC1 = 97%, FEFormate = 91%, and FECO = 6%) at −1.0 V vs. RHE with the current density of 108 mA cm−2 in a flow cell, and could still maintain excellent catalytic activity after 12 h of electrolysis. The shift in the electronic structure by the Zn-Bi bimetals synergistic effect was the primary reason for the remarkable catalytic activity. Density Functional Theory and In-situ ATR-SEIRAS showed that the charge redistribution caused by the Zn-Bi bimetals synergistic effect stabilizes the generation of HCOO* intermediates and promotes the conversion of CO2 to C1 products, especially formate.