Recent progress in bismuth-based materials for electrochemical CO₂ reduction to formate/formic acid

The electrochemical reduction of carbon dioxide (CO₂) to formate/formic acid represents a significant pathway for sustainable fuel production, addressing both environmental sustainability and the growing demand for renewable energy sources. Recently, bismuth-based (Bi-based) catalysts have attracted significant attention for this field due to their high selectivity, cost-effectiveness, and environmental friendliness. However, a critical challenge remains: developing catalysts that can achieve industrial-scale current density, high Faradaic efficiency, and robust stability simultaneously. Various emerging strategies have been explored to overcome this challenge. This review provides a comprehensive overview of recent advancements in this area. We begin with a discussion of the reaction mechanisms and theoretical optimization techniques for CO₂ reduction using Bi-based electrocatalysts. We then highlight recent optimization strategies for designing high-performance Bi-based catalysts, including approaches such as morphology control, crystal plane effects, doping engineering, interface engineering, and single-atom alloy engineering. Finally, we discuss future research directions for designing Bi-based catalysts capable of operating under industrial conditions for the electroreduction of CO₂ to formate/formic acid.