Single-Atom Ru Implanted on Co₃ O₄ Nanosheets as Efficient Dual-Catalyst for Li-CO₂ Batteries

Li-CO₂ battery has attracted extensive attention and research due to its super high theoretical energy density and its ability to fix greenhouse gas CO₂ . However, the slow reaction kinetics during discharge/charge seriously limits its development. Hence, a simple cation exchange strategy is developed to introduce Ru atoms onto a Co₃ O₄ nanosheet array grown on carbon cloth (SA Ru-Co₃ O₄ /CC) to prepare a single atom site catalyst (SASC) and successfully used in Li-CO₂ battery. Li-CO₂ batteries based on SA Ru-Co₃ O₄ /CC cathode exhibit enhanced electrochemical performances including low overpotential, ultra high capacity, and long cycle life. Density functional theory calculations reveal that single atom Ru as the driving force center can significantly enhance the intrinsic affinity for key intermediates, thus enhancing the reaction kinetics of CO₂ reduction reaction in Li-CO₂ batteries, and ultimately optimizing the growth pathway of discharge products. In addition, the Bader charge analysis indicates that Ru atoms as electron-deficient centers can enhance the catalytic activity of SA Ru-Co₃ O₄ /CC cathode for the CO₂ evolution reaction. It is believed that this work has important implications for the development of new SASCs and the design of efficient catalyst for Li-CO₂ batteries.