RuO(x) Quantum Dots Loaded on Graphdiyne for High-Performance Lithium-Sulfur Batteries.

Here, a strategy to strengthen d-p orbital hybridization by fabricating π backbonding in the catalyst for efficient lithium polysulfides (LiPSs) conversion is reported. A special interface structure of RuO quantum dots (QDs) anchored on graphdiyne (GDY) nanoboxes (RuO QDs/GDY) is prepared to enable strong Ru-to-alkyne π backdonation, which effectively regulates the d-electron structures of Ru centers to promote the d-p orbital hybridization between the catalyst and LiPSs and significantly boosts the catalytic performance of RuO QDs/GDY. The strong affinity with Li ions and fast Li-ion diffusion of RuO QDs/GDY also enable ultrastable Li metal anodes. Thus, S@RuO QDs/GDY cathodes exhibit excellent cycling performance under harsh conditions, and Li@RuO QDs/GDY anodes show an ultralong cycling life over 8800 h without Li dendrite growth. Lithium-sulfur (Li-S) full cells with S@RuO QDs/GDY cathodes and Li@RuO QDs/GDY anodes can deliver an impressive areal capacity of 17.8 mA h cm and good cycling stability under the practical conditions of low negative-to-positive electrode capacity (N/P) ratio N/P = 1.4, lean electrolyte E/S = 3 µL mg, and high S mass loading (15.4 mg cm ).