N, S Co-doped carbon anchored Co9S8 cathode: Advancing sustainable energy through efficient Li–CO2 Mars batteries

Abstract

Owing to their higher capacity and ability to address global warming, Li–CO2 batteries have potential for next-generation energy storage systems on Earth and for space applications. However, the key drawbacks of high overpotential and low cyclability of Li–CO2 batteries substantially hinder their practicality. In this study, we develop uniquely designed cobalt sulfide (Co9S8) nanoparticles anchored onto the N, S dual-doped hetero atoms graphitized mesoporous carbon (NSC) as a low-cost but highly effective cathodic catalyst for Li–CO2 batteries with a large number of active sites with enhanced conductivity. The as-developed Li–CO2 batteries under simulated Martian gas atmosphere conditions (Li–CO2 Mars) display a high discharge capacity and exceptional rate performance. The Li–CO2 Mars battery offers a high discharge capacity of 15147 mAh g−1 at 500 mA g−1 current density and maintains a stable performance over 120 cycles for a limited capacity of 500 mAh g−1. Further, the first-principle calculations provide a deeper understanding of the reaction pathways during discharging and charging. These results create new avenues for designing novel catalysts for high-performance Li–CO2 Mars batteries for their use in interplanetary missions.