Formate Fuel Production from the Electroreduction of CO2 on Nanostructured SnOx Coated on Gas Diffusion Electrode

Abstract

In this work, SnOx nanocatalyst has been successfully synthesized by a simple hydrothermal reaction method, which was then applied in the electrochemical reduction of CO2 to formate in 0.5 M KHCO3 aqueous solution. The SnCl2 .2H2O and CO(NH2)2 were used as the catalyst precursors, and PVP was used as protection reagent. The obtained catalyst was coated on gas diffusion electrode (GDE) to form the working electrode (SnOx/GDE). The SnOx nanocatalysts were synthesized at different temperatures (from 120～200oC), in order to investigate the influence of temperature on the produced catalysts’ catalytic activities. It was found that the SnOx(140-12) nanocatalyst performs best in terms of catalystic activity and Faradaic efficiency. The approached electrolysis potential of CO2 reduction indicated that the Faradaic efficiency of format exhibits a maximum value of 36% at the potential of -1.5 V vs. SHE.