Research progress on the reaction mechanism, metal-based catalysts, and reactors for CO2 electroreduction to formic acid/formate

The electrocatalytic CO₂ reduction reaction (CO₂RR) is a promising method for converting CO₂ into valuable chemicals and has gained significant attention. This paper first reviews the reaction mechanism of CO₂ reduction to formate, analyzing key intermediates and possible pathways. It then examines the synthesis and catalytic performance of metal catalysts, including Sn, Bi, In, Pb, and Sb. Various strategies to enhance CO₂RR efficiency, such as heteroatom doping, alloying, defect engineering, and surface modification, are discussed, focusing on improving intermediate adsorption and reaction kinetics by tuning the catalyst's electronic structure and surface properties. Additionally, the paper covers performance optimization through reactor control and electrolyzer design. Despite progress in catalyst development and mechanism understanding, challenges remain in selectivity, stability, scalability, and economic feasibility. Future research directions for commercializing CO₂RR technology and addressing global energy and environmental issues are also explored.