Sn/nitrogen-doped carbon composites with enhanced CO2 electroreduction toward formate

Abstract

Electrochemical CO₂ reduction reaction (CO₂RR) using renewable energy resources is a promising method for both mitigating the atmospheric CO₂ level and producing valuable chemicals. The morphology design and interface charge transfer of catalysts play a critical role in the activity and selectivity of CO₂RR. Herein, Sn@nitrogen-doped carbon (Sn@NC) was successfully developed by the loading procedure, enabling the direct conversion of CO₂ to C₁ products with excellent electrocatalytic performances. The target electrocatalyst Sn@NC-700 exhibits a high Faradaic efficiency of up to 93.2 % for formate product, with a partial current density of 22.3 mA cm^-2 at -1.03 V versus RHE. Moreover, the Sn@NC-700 electrocatalyst has remarkable stability in generating formate during CO₂RR, without obvious attenuation over the reaction time of 50 h. The electrochemical data and density functional theory calculations indicate that the inherent structural features, such as superior conductivity and rapid charge transfer, promote the Sn@NC electrode to stabilize the *OCHO intermediates, thereby accelerating the production of formate. This study is beneficial for reducing carbon emissions, promoting resource recycling, and advancing a green and sustainable production of formate to serve the chemical industry.