TiO2 Nanosheet-Redox Graphene Oxide/Sulphur Cathode for High-Performance Lithium-Sulphur Batteries

Lithium-sulphur batteries are considered as some of the most potent secondary-battery systems. These batteries are expected to have extensive applications in fields requiring high-energy density. However, such applications are hindered by some serious intrinsic obstacles. Herein, TiO2 nanosheets-rGO/sulphur (TiO2 NS-rGO/S) composites were fabricated through a two-process hydrothermal method. TiO2 nanosheets served as active sites for polysulphide absorption, whereas rGO offered space for sulphur improvement and TiO2 NS-rGO/S composites. The TiO2 NS-rGO/S composite exhibited high discharge capacity of 1099 mAh.g(-1) at 0.2 C rate and retained a capacity of 690 mAh.g(-1) after 100 cycles, with high sulphur loading of 3 mg.cm(-2). The high initial specific discharge capacity and improved cyclic stability were attributed to the synergistic effects of TiO2 nanosheets and rGO. These results indicated that the simple, low-cost and scalable method provides a novel perspective on practical utilisation of lithium-sulphur batteries.