Safe and stable Li–CO₂ battery with metal-organic framework derived cathode composite and solid electrolyte

Li–CO₂ batteries receive wide attention due to their strategic utilization of CO₂ and high energy density. However, their practical application is hindered by sluggish kinetics and safety hazards. Herein, a stable and highly conductive ceramic-based solid electrolyte (Li_1.4Al_0.4Ti_1.6(PO₄)₃) is used to enhance the safety aspect. In contrast, a metal-organic framework (MOF) based catalyst is introduced to ensure low polarization and long cycle life for Li–CO₂ batteries. The as-prepared Li–CO₂ cell delivers an outstanding maximum specific capacity of 6698 mA h g⁻¹ at 100 mA g⁻¹ current density. Besides, the cell shows a stable performance over 100 cycles of charge-discharge with a cut-off capacity of 500 mA h g⁻¹. Later, the post-cycling analysis is performed to evaluate the electrode degradation mechanism. Further, to understand the interactions between the Co₃O₄-based catalyst and carbon-based host electrode with discharge product, we perform first-principles calculations based on density functional theory. This work shows great potential for the use of MOF cathode catalyst in Li–CO₂ battery and is believed to be particularly promising for a stable operation.