Enhancement of formic acid formation by nitrogen-doped graphene oxide nanosheets decorated with Sn nanoparticles in electrochemical CO2 reduction

Abstract

Electrochemical conversion of CO₂ into renewable fuels is a critical area of research that poses significant scientific challenges. Herein, we investigated the impact of oxygen functional groups on the graphene support material in Sn/graphene composites. We discovered that the electrocatalytic performance of these composites could be adjusted by altering the structure of the metals and the support material, specifically graphene oxide. Our results revealed that Sn nanoparticles anchored on epoxy-functionalized graphene oxide facilitated the efficient generation of formic acid, achieving a remarkable faradaic efficiency (FE) of 75% and a high current density of −20 mA cm⁻² at 1.6 V vs. Ag/AgCl. The use of the gas diffusion electrode coupled with Sn/graphene composites was effective in reducing CO₂. Notably, the interaction between Sn and the support material played a vital role in determining the catalytic activity and selectivity of the formic acid. This study underscores the crucial role of support materials in electrocatalytic performance and offers insights into how to tailor the support material to optimize the conversion of CO₂ into renewable fuels.