Fast decomposition of Li₂CO₃/C actuated by single-atom catalysts for Li-CO₂ batteries

Lithium carbon dioxide (Li-CO₂) batteries deliver a theoretical energy density of 1876 W h kg⁻¹ in terms of effective utilization of greenhouse gases. This battery system is considered to be an encouraging electrochemical energy storage device and a promising alternative to Li-ion batteries. However, the main drawback of Li-CO₂ batteries is their accumulative discharge product of Li₂CO₃/C, which leads to large overpotential and poor cycling performance. Thus, specific and efficient catalysts must be explored to enhance the decomposition of Li₂CO₃/C. Single-atom catalysts (SACs) are regarded as promising heterogeneous catalysts owing to their maximized utilization of metal atoms and strong interfacial electronic interactions. Herein, single-metal atoms of Fe, Co, and Ni uniformly anchored on N-doped reduced graphene oxide (rGO), designated as Fe₁/N-rGO, Co₁/N-rGO, and Ni₁/N-rGO, respectively, are designed and fabricated to investigate their catalytic activity toward the decomposition of Li₂CO₃/C. Among them, Fe₁/N-rGO delivers a high discharge capacity of 16,835 mA h g⁻¹ at 100 mA g⁻¹ and maintains stability for more than 170 cycles with a discharge voltage of 2.30 V at 400 mA g⁻¹. Therefore, this catalysts are overwhelmingly superior to other types. This work reveals the advances of SACs in Li-CO₂ batteries and offers an effective method for realizing high-performance Li-CO₂ batteries.