Bimetallic RuNi Electrocatalyst Coated MWCNTs Cathode for an Efficient and Stable Li-CO and Li-CO Batteries Performance with Low Overpotential.

Rechargeable lithium-CO (Li-CO ) batteries are an attractive energy storage technology that can reduce fossil fuel usage and limit the adverse environmental impact of CO 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-CO 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 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 with a fixed 500 mAh g capacity. Furthermore, Mars exploration is made feasible with the Li-CO battery composed of the RuNi/MWCNTs as cathode catalyst, which performs very similarly to that of pure CO atmosphere. This approach may simplify the process of developing high-performance Li-CO batteries to achieve carbon negativity on Earth and for future interplanetary Mars missions.