Zhao Xufeng, Zhu Mengqi, Tang Conggu, Quan Kechun, Tong Qingsong, Cao Hewei, Jiang Jiacheng, Yang Hongtao, Zhang Jindan
College of Chemistry and Materials Science, Fujian Provincial University Engineering Research Center of Efficient Battery Modules, Fujian Key Laboratory of Polymer Materials, Fujian Normal University, 32 Shangsan Road, Fuzhou 350007, China.
College of Chemistry and Materials Science, Fujian Provincial University Engineering Research Center of Efficient Battery Modules, Fujian Key Laboratory of Polymer Materials, Fujian Normal University, 32 Shangsan Road, Fuzhou 350007, China.
J Colloid Interface Sci. 2022 Aug 15;620:478-485. doi: 10.1016/j.jcis.2022.04.018. Epub 2022 Apr 8.
Though polymer electrolytes have been regarded as promising separators for solid-state lithium metal batteries, their low ionic conductivity, poor thermostability and inflammability limit their practical applications. Herein, a polymer composite electrolyte consisting of metal-organic frameworks modified TiC-MXene nanosheets (ZIF-8@MXene) and polymer mixture (PE-ZIF-8@MXene) was fabricated. The fabricated nonflammable ZIF-8@MXene nanosheets have abundant functional groups and Lewis acid sites as well as high specific surface area. In the composite electrolyte, ZIF-8@MXene nanosheets increased the dissociation of lithium salts and provided channels for transporting ions, accelerating the Li ion transportation. They also enhanced the tensile strength, thermostability and flame resistance of PE-ZIF-8@MXene. Consequently, the fabricated flame-retardant PE-ZIF-8@MXene presented high ionic conductivity (4.4 mS cm), impressive Li transference number (0.76) and enhanced tensile strength (3.77 MPa). In addition, the assembled Li|PE-ZIF-8@MXene|Li had a long cycle life of 2000 h, and Li|PE-ZIF-8@MXene|LiFePO batteries displayed a capacity retention of 89.6% after 500 cycles.
尽管聚合物电解质被认为是固态锂金属电池有前景的隔膜，但其低离子电导率、较差的热稳定性和易燃性限制了它们的实际应用。在此，制备了一种由金属有机框架修饰的TiC-MXene纳米片（ZIF-8@MXene）和聚合物混合物（PE-ZIF-8@MXene）组成的聚合物复合电解质。所制备的不可燃ZIF-8@MXene纳米片具有丰富的官能团和路易斯酸位点以及高比表面积。在复合电解质中，ZIF-8@MXene纳米片增加了锂盐的解离并提供了离子传输通道，加速了锂离子传输。它们还提高了PE-ZIF-8@MXene的拉伸强度、热稳定性和阻燃性。因此，所制备的阻燃PE-ZIF-8@MXene具有高离子电导率（4.4 mS cm）、令人印象深刻的锂迁移数（0.76）和增强的拉伸强度（3.77 MPa）。此外，组装的Li|PE-ZIF-8@MXene|Li具有2000小时的长循环寿命，Li|PE-ZIF-8@MXene|LiFePO4电池在500次循环后容量保持率为89.6%。
