Multifunctional Quasi‐Homogeneous Catalysts as a New Catalytic Strategy to Boost the Performance of Li‐O2 Batteries

Abstract Li‐O 2 batteries have been considered as a kind of prospective next‐generation batteries due to their ultrahigh energy densities. However, limited capacities, high charge overpotentials, and short lifetime are troubling obstacles for realizing their real‐world implementation. Common strategies, including introducing solid‐state catalysts (SSCs) and redox mediators (RMs), are insufficient to solve these issues. Herein, Ru‐loaded amino‐phenanthroline‐based carbonized polymer dots (RuApCPDs) integrating the catalytic activity of SSCs with the mobility of RMs have been designed to behave as quasi‐homogeneous catalysts in the electrolyte. Their mobile nature can ensure the avoidance of complete coverage of active sites, and the catalytic ability decreases the charge overpotential through co‐deposition with the discharge products. Additionally, the RuApCPDs can also adjust the Li + solvation structure and well protect the Li metal anodes with high stability. As a result, the introduction of RuApCPDs leads to a fivefold increase in discharge capacity, a low charge voltage of 3.75 V, and a running life of 168 cycles (79 cycles without RuApCPDs). The multifunctional quasi‐homogeneous catalyst developed here demonstrates its advantageous potential as a new catalytic strategy for bringing Li‐O 2 batteries to become a viable technology.