Pd-Doped In2O3 for CO2 Electroreduction to Ethanol through CO Binding Regulation

Abstract

Renewable energy driven electrochemical carbon dioxide reduction (CO₂RR) to alcohols provides an effective pathway for achieving carbon neutrality and sustainable development. However, it is challenging to convert CO₂ into ethanol due to the sluggish C−C coupling and complex 12 electron/proton transferred process, which has been achieved mainly on Cu catalysts but with poor selectivity. Herein, In₂O₃ catalysts were doped with small amount of Pd and exhibited high activity for CO₂RR to ethanol with a high Faradaic efficiency (50.7 %) at low overpotential. The introduction of Pd promotes the transformation of reaction products from formic acid to ethanol by modulating the binding strength of *CO intermediates. The in-situ ATR-SEIRAS and DFT calculations proved that the formation of Pd−O−In could modulate the binding strength of *CO and enhanced its coverage, thus facilitating C−C coupling step towards ethanol. This study may provide a new strategy to the generation of high value-added products from CO₂ over Non-Cu-based catalysts.