Highly efficient In–Sn alloy catalysts for electrochemical reduction of CO2 to formate

Abstract

Gas diffusion electrodes (GDEs), including GDE-In0.90Sn0.10, GDE-In0.47Sn0.53 and GDE-In0.22Sn0.78, were prepared by electrodeposition of In–Sn alloys on carbon fiber paper, and then used to explore the electroreduction of CO2 to formate in aqueous solution. Compared with commercial indium or Sn foil catalysts, the GDE-In0.90Sn0.10 electrode in particular is shown to have excellent catalytic performance towards electroreduction of CO2 to formate, with a high Faradaic efficiency (~92%). More importantly, the catalytic activity of GDE-In0.90Sn0.10 remained reasonably stable over a 22-hour period of electrolysis, and a relatively high electrolytic current density (15mAcm−2) was obtained in an aqueous medium, demonstrating its potential for electrochemical reduction of CO2 to formate.