Jia Yuncan, Chen Shang, Meng Xiaodong, Peng Xiaomeng, Zhou Ji, Zhang Jiawen, Hong Song, Zheng Lirong, Wang Zhongli, Bielawski Christopher W, Geng Jianxin
State Key Laboratory of Organic-Inorganic Composites, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, 15 North Third Ring East Road, Chaoyang District, Beijing, 100029, China.
State Key Laboratory of Separation Membranes and Membrane Processes, Tianjin Key Laboratory of Advanced Fibers and Energy Storage, School of Material Science and Engineering, Tiangong University, No. 399 BinShuiXi Road, XiQing District, Tianjin, 300387, China.
Small. 2023 Nov;19(47):e2303919. doi: 10.1002/smll.202303919. Epub 2023 Jul 24.
Lithium-sulfur (Li-S) batteries hold great promise for widespread application on account of their high theoretical energy density (2600 Wh kg ) and the advantages of sulfur. Practical use, however, is impeded by the shuttle effect of polysulfides along with sluggish cathode kinetics. it is reported that such deleterious issues can be overcome by using a composite film (denoted as V-CMP@MWNT) that consists of a conjugated microporous polymer (CMP) embedded with vanadium single-atom catalysts (V SACs) and a network of multi-walled carbon nanotubes (MWNTs). V-CMP@MWNT films are fabricated by first electropolymerizing a bidentate ligand designed to coordinate to V metals on self-standing MWNT films followed by treating the CMP with a solution containing V ions. Li-S cells containing a V-CMP@MWNT film as interlayer exhibit outstanding performance metrics including a high cycling stability (616 mA h g at 0.5 C after 1000 cycles) and rate capability (804 mA h g at 10 C). An extraordinary area-specific capacity of 13.2 mA h cm is also measured at a high sulfur loading of 12.2 mg cm . The underlying mechanism that enables the V SACs to promote cathode kinetics and suppress the shuttle effect is elucidated through a series of electrochemical and spectroscopic techniques.
锂硫（Li-S）电池因其高理论能量密度（2600 Wh kg）和硫的优势而具有广泛应用的巨大潜力。然而，多硫化物的穿梭效应以及缓慢的阴极动力学阻碍了其实际应用。据报道，通过使用一种复合膜（表示为V-CMP@MWNT）可以克服这些有害问题，该复合膜由嵌入钒单原子催化剂（V SACs）的共轭微孔聚合物（CMP）和多壁碳纳米管（MWNTs）网络组成。V-CMP@MWNT膜的制备方法是，首先在自立式MWNT膜上电聚合一种设计用于与V金属配位的双齿配体，然后用含V离子的溶液处理CMP。含有V-CMP@MWNT膜作为中间层的Li-S电池表现出出色的性能指标，包括高循环稳定性（在0.5 C下1000次循环后为616 mA h g）和倍率性能（在10 C下为804 mA h g）。在12.2 mg cm的高硫负载下，还测得13.2 mA h cm的非凡面积比容量。通过一系列电化学和光谱技术阐明了V SACs促进阴极动力学并抑制穿梭效应的潜在机制。
