Synthesis of Co-Mo2C nanoparticles decorated three-dimensional N-doped graphene composite as an efficient cathode catalyst for Li–CO2 batteries

Abstract

Li–CO₂ batteries (LCBs) stand out as promising candidates for high-energy-density storage solutions, capturing widespread interest and research focus. However, the high charging voltage and poor cycling stability owing to the sluggish reaction kinetics of carbon dioxide reduction seriously limit the commercialization of LCBs. Herein, a composite of cobalt and molybdenum carbide nanoparticles decorated three-dimensional N-doped graphene was fabricated as an efficient cathode catalysts for LCBs . The porous structure and large specific surface area of graphene substrate provide abundant catalytic active sites and sufficient deposition space for discharge products. The co-catalytic effect of cobalt-molybdenum carbide bimetal greatly enhances the CO₂ reaction kinetics. The assembled LCBs exhibited a ultrahigh discharge capacity of 27,886 mAh g⁻¹ at 100 mA g⁻¹, a long cycle life of 248 cycles (limited capacity of 500 mAh g⁻¹), and a low overpotential of 1.56 V. This research presents a practical approach to developing highly effective cathode catalysts, aiming to enhance the operational efficiency of LCBs.