Synergistic Cu-based catalysts with multiple active sites for high-efficiency Li-CO2 batteries.

The lithium-carbon dioxide (Li-CO2) battery is a promising energy storage technology that integrates CO2 utilization with energy storage and conversion. However, its development is hindered by slow reaction kinetics and insulating Li2CO3 discharge products deposited at the cathode, which cause severe polarization and rapid capacity degradation. Herein, novel Cu-based catalysts with multiple active sites anchored on nitrogen-doped carbon (Cu/NC) are developed to achieve highly efficient Li-CO2 batteries. Metallic Cu nanoparticles facilitate efficient electron transfer during the CO2 reduction reaction (CO2RR), while the induced Cu-N/O dual active sites effectively reduce the energy barrier for decomposing discharge products. Furthermore, the optimized N configurations in the NC matrix enhance the intrinsic activity of the catalytic sites. Consequently, the Li-CO2 battery incorporating the optimized catalyst demonstrates attractive cycling stability over 850 h at 300 mA g-1, with a remarkably low overpotential of 1.30 V, showing great potential for low-cost and highly efficient Li-CO2 batteries. This work provides a strategic route for designing cost-effective multi-active-site catalysts, offering critical insights into the development of high-performance Li-CO2 batteries.