Abstract
Li-CO2 batteries (LCBs) have garnered significant attention due to their impressive high-energy densities and unique carbon storage capability. However, the sluggish transformation kinetics of CO2 induced high overpotential and poor cycle life greatly impeding the practical application of LCBs. The imperative task for the development of advanced LCBs is to design a bidirectional catalyst with remarkable catalytic activity, selectivity and exceptional electrochemical stability. In this review, the charge and discharge reaction mechanisms of LCBs are systematically presented, and various reaction pathways may occur based on specific reaction conditions. Then the scale and morphology regulation strategies of metal-based catalysts are highlighted, which include their effect on electronic states, coordination environments, and adsorption strengths. The recent progress of promising catalysts with different nanostructures is systematically addressed. Finally, the critical challenges and perspectives for scale and morphology design of metal-based catalysts in LCBs are discussed.