Wang Yuqi, Yue Bin, Wang Yafei, Wang Jinxian, Ma Qianli, Liu Guixia, Yu Wensheng, Dong Xiangting
Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.
Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China; Chongqing Research Institute, Changchun University of Science and Technology, Chongqing 401135, China.
J Colloid Interface Sci. 2024 Sep;669:83-94. doi: 10.1016/j.jcis.2024.04.229. Epub 2024 May 1.
The shuttle effect of lithium polysulfides (LiPSs) and the sluggish reaction kinetics of LiPSs conversion pose serious challenges to the commercial feasibility of lithium-sulfur (Li-S) batteries. To address these obstacles, herein, we construct CeO/Co heterostructures in hollow necklace-like carbon fibers (CeO/Co-CNFs) as the cathode host material for Li-S batteries. The specific surface area of fibers is significantly enhanced by using a template, thereby promoting the utilization efficiency of sulfur. Meanwhile, CeO/Co-CNFs show strong conductivity, effective adsorption to LiPSs, and robust catalytic activity for LiPSs conversion. As a result, the Li-S battery with CeO/Co-CNFs displays 961 mAh g at 0.2 C, with an 86 % capacity retention rate after 100 cycles. At 2.0 C current density, the composite cathode maintains an initial discharge capacity of 782 mAh g, with a mere 0.044 % capacity loss per cycle. Furthermore, in situations with limited electrolytes, high sulfur loading, and high areal mass loading, the composite cathode can provide a high areal capacity of 6.2 mg cm over 100 cycles. This work provides a useful approach for investigating high-performance Li-S battery cathodes.
多硫化锂（LiPSs）的穿梭效应以及LiPSs转化反应动力学迟缓对锂硫（Li-S）电池的商业可行性构成了严峻挑战。为克服这些障碍，在此我们构建了中空项链状碳纤维中的CeO/Co异质结构（CeO/Co-CNFs）作为Li-S电池的正极主体材料。通过使用模板显著提高了纤维的比表面积，从而提升了硫的利用效率。同时，CeO/Co-CNFs表现出强导电性、对LiPSs的有效吸附以及对LiPSs转化的强大催化活性。结果，采用CeO/Co-CNFs的Li-S电池在0.2 C下的比容量为961 mAh g，100次循环后容量保持率为86%。在2.0 C电流密度下，复合正极的初始放电容量保持在782 mAh g，每循环容量损失仅0.044%。此外，在电解质有限、硫负载量高和面积质量负载高的情况下，复合正极在100次循环中可提供6.
