摘要：Electroreduction of CO2 to formic acid (ERCF) based on gas diffusion electrodes (GDEs) has been considered as a promising method to convert CO2 into value-added chemicals. However, current GDEs for ERCF suffer from low efficiency of electron transfer. In this work, a novel Sn-based gas diffusion electrode (ESGDE) is prepared by electrodepositing Sn on Nafion-bonded carbon black as catalyst layer to enhance electron transfer and thus the efficiency of ERCF. The highest Faraday efficiency (73.01 ± 3.42%), current density (34.21 ± 1.14 mA cm-2) and production rate (1772.81 ± 59.08 μmol m-2 s-1) of formic acid are obtained by using the ESGDE with electrodeposition time of 90 s in 0.5 M KHCO3 solution, which are one of the highest values obtained from Sn-based gas diffusion electrodes under similar conditions. The notable efficiency of ERCF achieved here should be attributed to the enhancement in the reactants transfer as well as the three-dimensional reaction zone. This work will be helpful for the industrial application of GDEs in EFCF.
