Efficient photoelectrocatalytic reduction of CO2 to formate via Bi-doped InOCl nanosheets

Converting CO2 into useful substances is an important approach to address the challenge of reducing CO2 emissions and combating climate change. Compared with the traditional process, photoelectrocatalytic CO2 reduction has great potential to solve the problem of CO2 emission. In this work, Bi-doped InOCl cathode catalysts were prepared by a two-step calcination process, and they demonstrated efficient catalytic activity for the reduction of CO2 to formate. The inclusion of bismuth (Bi) in InOCl resulted in improved catalytic performance compared to the native InOCl catalyst. Specifically, the highest formate selectivity can be observed at -0.9 V vs RHE with a Faraday efficiency of 89.9% and the product rate of 101.41 μmol h–1cm–2 when the Bi doping amount is 5%, representing approximately 2 and 3 times the values obtained with native InOCl, respectively. The experimental results indicate that Bi doping promotes the formation of {001} crystalline surfaces in InOCl, while increasing the specific surface area and the availability of more active sites for CO2 reduction. This work holds significant potential for further advancements in the field of photoelectrocatalytic reduction of CO2.