Interface-induced polymerization strategy for constructing titanium dioxide embedded carbon porous framework with enhanced chemical immobilization towards lithium polysulfides

The shuttle effect induced by soluble lithium polysulfides (LiPSs) is known as one of the crucial issues that limit the practical applications of lithium-sulfur (Li-S) batteries. Herein, a titanium dioxide nanoparticle embedded in nitrogen-doped porous carbon nanofiber (TiO₂@NCNF) composite is constructed via an interface-induced polymerization strategy to serve as an ideal sulfur host. Under the protection of the nanofiber walls, the uniformly dispersed TiO₂ nanocrystalline can act as capturing centers to constantly immobilize LiPSs towards durable sulfur chemistry. Besides, the mesoporous microstructure in the fibrous framework endows the TiO₂@NCNF host with strong physical reservation for sulfur and LiPSs, sufficient pathways for electron/ion transfer, and excellent endurance for volume change. As expected, the sulfur-loaded TiO₂@NCNF composite electrode presents a fabulous rate performance and long cycle lifespan (capacity fading rate of 0.062% per cycle over 500 cycles) at 2.0 C. Furthermore, the assembled Li-S batteries harvest superb areal capacity and cycling stability even under high sulfur loading and lean electrolyte conditions.