Hong Shu, Han Yunzhao, Zhang Kun, Wang Mingbo, Cui Nana, Du Xiaoqinq, Li Qingyu, Huang Youguo, Jiang Feng, Xie Keyu
School of Materials Science and Engineering, Central South University, Changsha, Hunan 410083, P. R. China.
State Key Laboratory of Solidification Processing, Center for Nano Energy Materials, School of Materials Science and Engineering, North-Western Polytechnical University and Shaanxi Joint Laboratory of Graphene (NPU), Xi)an 710072, P. R. China.
J Nanosci Nanotechnol. 2020 Mar 1;20(3):1715-1722. doi: 10.1166/jnn.2020.16957.
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 at 0.2 C rate and retained a capacity of 690 mAh·g after 100 cycles, with high sulphur loading of 3 mg·cm. 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.
锂硫电池被认为是一些最具潜力的二次电池系统。这些电池有望在需要高能量密度的领域得到广泛应用。然而，此类应用受到一些严重的内在障碍的阻碍。在此，通过两步水热法制备了TiO₂纳米片-rGO/硫（TiO₂ NS-rGO/S）复合材料。TiO₂纳米片作为多硫化物吸收的活性位点，而rGO为硫的改进和TiO₂ NS-rGO/S复合材料提供了空间。TiO₂ NS-rGO/S复合材料在0.2 C倍率下表现出1099 mAh·g的高放电容量，在100次循环后仍保持690 mAh·g的容量，硫负载量高达3 mg·cm。高初始比放电容量和改善的循环稳定性归因于TiO₂纳米片和rGO的协同效应。这些结果表明，这种简单、低成本且可扩展的方法为锂硫电池的实际应用提供了新的视角。
