Zhao Yuliang, Wang Yiyang, Xue Wenjuan, Cheng Ruyi, Zheng Xuan, Zhu Gengcong, Hu Dayin, Huang Hongliang, Hu Chuangang, Liu Dong
State Key Laboratory of Organic-Inorganic Composites, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China.
State Key Laboratory of Separation Membranes and Membrane Processes, School of Chemical Engineering and Technology, Tiangong University, Tianjin, 300387, P. R. China.
Adv Mater. 2024 Aug;36(31):e2403097. doi: 10.1002/adma.202403097. Epub 2024 May 25.
Rechargeable Zinc-iodine batteries (ZIBs) are gaining attention as energy storage devices due to their high energy density, low-cost, and inherent safety. However, the poor cycling performance of these batteries always arises from the severe leakage and shuttle effect of polyiodides (I and I ). Herein, a novel cationic pyridine-rich covalent triazine framework (CCTF-TPMB) is developed to capture and confine iodine (I) species via strong electrostatic interaction, making it an attractive host for I in ZIBs. The as-fabricated ZIBs with I loaded CCTF-TPMB (I@CCTF-TPMB) cathode achieve a large specific capacity of 243 mAh g at 0.2 A g and an exceptionally stable cyclic performance, retaining 93.9% of its capacity over 30 000 cycles at 5 A g. The excellent electrochemical performance of the ZIBs can be attributed to the pyridine-rich cationic sites of CCTF-TPMB, which effectively suppress the leakage and shuttle of polyiodides, while also accelerating the conversion reaction of I species. Combined in situ Raman and UV-vis analysis, along with theoretical calculations, clearly reveal the critical role played by pyridine-rich cationic sites in boosting the ZIBs performances. This work opens up a promising pathway for designing advanced I cathode materials toward next-generation ZIBs and beyond.
可充电锌碘电池（ZIBs）因其高能量密度、低成本和固有安全性，作为储能装置正受到关注。然而，这些电池较差的循环性能总是源于多碘化物（I⁻和I₃⁻）的严重泄漏和穿梭效应。在此，开发了一种新型的富含阳离子吡啶的共价三嗪框架（CCTF - TPMB），通过强静电相互作用捕获和限制碘（I）物种，使其成为ZIBs中碘的有吸引力的主体。所制备的负载碘的CCTF - TPMB（I@CCTF - TPMB）阴极的ZIBs在0.2 A g⁻¹时实现了243 mAh g⁻¹的大比容量和异常稳定的循环性能，在5 A g⁻¹下30000次循环后仍保留其容量的93.9%。ZIBs优异的电化学性能可归因于CCTF - TPMB富含吡啶的阳离子位点，其有效抑制了多碘化物的泄漏和穿梭，同时还加速了碘物种的转化反应。结合原位拉曼和紫外 - 可见分析以及理论计算，清楚地揭示了富含吡啶的阳离子位点在提升ZIBs性能中所起的关键作用。这项工作为设计用于下一代及更先进的ZIBs的先进碘阴极材料开辟了一条有前景的途径。
