Bimetallic RuNi Electrocatalyst Coated MWCNTs Cathode for an Efficient and Stable Li-CO₂ and Li-CO_{2 Mars} Batteries...

Rechargeable lithium-CO₂ (Li-CO₂ ) batteries are an attractive energy storage technology that can reduce fossil fuel usage and limit the adverse environmental impact of CO₂ emissions. However, the high charge overpotential, unstable cycling, and incomplete understanding of the electrochemical process limit its advancement for practical applications. Herein, we develop a Li-CO₂ battery by designing a bimetallic ruthenium-nickel catalyst onto multi-walled carbon nanotubes (RuNi/MWCNTs) catalyst as cathode by solvothermal method, which exhibits a lower overpotential of 1.15 V and a discharge capacity of 15,165 mAh g^-1 with outstanding coulombic efficiency of 97.4 %. The battery can also operate at high rates and have a stable cycle of more than 80 cycles at a current density of 200 mA g^-1 with a fixed 500 mAh g^-1 capacity. Furthermore, Mars exploration is made feasible with the Li-CO_{2 Mars} battery composed of the RuNi/MWCNTs as cathode catalyst, which performs very similarly to that of pure CO₂ atmosphere. This approach may simplify the process of developing high-performance Li-CO₂ batteries to achieve carbon negativity on Earth and for future interplanetary Mars missions.