Atomic design of bidirectional electrocatalysts for reversible Li-CO2 batteries

With the increasing demand for carbon neutrality, Li-CO2 batteries are a promising technology for using CO2 as an energy storage medium and have attracted extensive attention. However, the sluggish kinetics and complex reaction mechanism significantly affect the reversibility of Li-CO2 batteries, which has stimulated the study of reaction pathways, product regulations, and bidirectional catalysts. Modulating the structure of catalysts at the atomic level has attracted increasing attention recently for improving their selectivity and activity, thus accelerating reaction kinetics and regulating the reaction pathways. In this review, we systematically discuss the conversion reaction mechanisms and analyze the key factors that affect the reaction pathways during discharge and charge in Li-CO2 batteries. Then the strategies at the atomic level for developing efficient bidirectional catalysts are highlighted, including their features, advantages, and limitations. Finally, a summary and outlook on fundamental investigation and advanced catalysts development for high-performance Li-CO2 batteries are presented.