CuSnBi Catalyst Grown on Copper Foam by Co-Electrodeposition for Efficient Electrochemical Reduction of CO2 to Formate

Abstract

Effective electrochemical reduction of carbon dioxide to formate under mild conditions helps mitigate the energy crisis but requires the use of high-performance catalysts. The addition of a third metal to the binary metal catalyst may further promote the electrochemical reduction of carbon dioxide to formate. Herein, we provided a co-electrodeposition method to grow CuSnBi catalysts on pretreated copper foam and discussed the effects of both pH value and molar ratio of metal ions (Cu2+, Sn2+, and Bi3+) in the electrodeposition solution on the electrocatalytic performance of CO2 to HCOO−. When the pH value of the electrodeposition solution was 8.5 and the molar ratio of Cu2+, Sn2+, and Bi3+ was 1:1:1, the electrode showed the highest FEHCOO− of 91.79% and the formate partial current density of 36.6 mA·cm−2 at −1.12 VRHE. Furthermore, the electrode kept stable for 20 h at −1.12 VRHE, and FEHCOO− was always beyond 85% during the electrolysis process, which is excellent compared to the previously reported ternary metal catalytic electrodes. This work highlights the vital impact of changes (pH value and molar ratio of metal ions) in electrodeposition liquid on catalytic electrodes and their catalytic performance, and refreshing the electrolyte is essential to maintain the activity and selectivity during the electrochemical reduction of CO2 to HCOO−.

Efficient CO2 electroreduction to formate using Bi–Pb bimetallic catalysts with 2D vertical nanosheets

“…A promising way to maintain the high electroreduction performance over a wide electrochemical window is to tune the electronic structures of catalysts, such as heteroatom doping of a second metal element. 30–37 For example, the Bi metal salt was added to obtain a Bi–Sn bimetallic catalyst by NaBH 4 reduction in a solution containing metal Sn salts. 38,39 The Bi–Sn bimetallic catalyst with rich interfaces significantly improved the CO 2 electroreduction performance compared with the catalytic performance of metals Bi and Sn.…”