Active Anchoring Polysulfides of ZnS-Decorated Porous Carbon Aerogel for a High-Performance Lithium-Sulfur Battery

Graphical Anchored down : Ultrafine ZnS is successfully introduced into carbon aerogel (CA) to form a cathode for lithium–sulfur batteries. The nanoporous ZnS-CA composites present excellent electrochemical performances, owing to the ZnS nanoparticles having a strong affinity for Li 2 S n species. Furthermore, the strong affinity was validated by first-principles theory calculations; the results clearly reveal the anchoring and catalytic mechanism. A carbon aerogel composite modified with ZnS (ZnS-CA) was successfully prepared through a simple in situ synthesis and used as a cathode for lithium-sulfur batteries. The nanopore ZnS-CA composites with a high specific surface area and rich mesoporous structure exhibit stronger adsorption and immobilization ability for polysulfides. The ZnS-CA/S cathode materials offer excellent electrochemical performances with lasting cycling stability and high specific capacity. In particular, the 6ZnS-CA/S sample achieves an initial capacity of 1352 mAh g −1 at 0.2 C and maintains a high capacity of 1119 mAh g −1 after 100 cycles. Furthermore, after 300 long cycles, it still maintains a high capacity of 730 mAh g −1 at 1 C. These excellent performance features are attributed to the strong affinity of ZnS for Li 2 S n species, thus polysulfide shuttling can be effectively inhibited from the cathode source. Furthermore, the strong adsorption energy between ZnS and polysulfides was validated by using first-principles theory calculations, which reveals the anchoring and catalytic mechanism.