Gas-phase CO2 electroreduction over Sn–Cu hollow fibers

Abstract

CO₂ electroreduction to value-added chemicals by virtue of renewable electricity is significant for carbon emission abatement and renewable energy conversion/storage. Conventional CO₂ electroreduction occurring in aqueous solution or ionic liquid suffers from insufficient CO₂ solubility and a separation dilemma of the soluble products. In this work, we report that when using Sn–Cu hollow fiber electrodes, gas-phase CO₂ can be directly electroreduced into various multicarbon oxygenates. The faradaic efficiencies of acetaldehyde and acetone over a 0.3 wt% Sn–Cu hollow fiber electrode are 10 and 12% at the cell voltage of −1.4 V. The presence of an appropriate amount of SnO₂ nanoparticles decorated on a Cu hollow fiber surface not only facilitates the reaction kinetics with elevated current densities, but also improves the C–C coupling of intermediates, promoting the formation of multicarbon oxygenates.