A versatile nano-TiO_(2) decorated gel separator with derived multi-scale nanofibers towards dendrite-blocking and polysulfide-inhibiting lithium-metal batteries  

作　　者：Huijuan Zhao jing Yan Nanping Deng Weimin Kang Bowen Cheng 

机构地区：[1]State Key Laboratory of Separation Membranes and Membrane Processes/National Center for International Joint Research on Separation Membranes,Tiangong University,Tianjin 300387,China [2]School of Textile Science and Engineering,Tiangong University,Tianjin 300387,China

出　　处：《Journal of Energy Chemistry》2021年第4期190-201,共12页能源化学（英文版）

基　　金：supported by the National Natural Science Foundation of China(51678411);the National Key Technology R&D Program(2016YFB0303300);the Science and Technology Plans of Tianjin(Nos.19PTSYJC00010 and 18PTSYJC00180)。

摘　　要：In this study,a versatile fluorine-bearing gel membrane with multi-scale nanofibers was rationally designed and synthesized via facile one-step blend electrospinning of nano-titanium dioxide(TiO_(2))particles and fluorinated poly-m-phenyleneisophthalamide(PMIA)polymer solution.The prepared multiscale TiO_(2)-assisted gel separator presented relatively high porosity,small aperture,giving rise to superior affinity to electrolyte and sufficient active sites to accelerate lithium ions migration.Meanwhile,the asfabricated multifunctional GPE also rendered outstanding heat-resistance and well-distributed lithiumions flux,and the mutual overlaps between the coarse fibers and the fine fibers within the multi-scale nanofiber membrane provided a strong skeleton support,which in turn laid a solid footing stone for high-security and dendrite-proof batteries.Particularly,the nano-TiO_(2) particles within PMIA membrane acted as"gatekeepers",which can not only resist the growth of lithium dendrites,but also intercept the dissolved polysulfide on cathode side.Based on these merits,the gel PMIA-based lithium cobalt(LCO)/lithium battery obtained the remarkably improved rate capability and cycle performances on account of superior ionic conductivity,steady anodic stability window and weakened polarization behavior.Meanwhile,the resultant lithium-sulfur cell also delivered the outstanding cycling stability with the aid of the greatly prevented"shuttle effect"of dissolved lithium polysulfides based on the physical trapping and chemical binding of the prepared GPE to polysulfides species.This work proved that the addition of functional inorganic nanoparticles similar with TiO_(2) in multi-scale gel PMIA membrane can enhance the lithium ions transport capability,resist the growth of lithium dendrites as well as inhibit the shuttle effect of polysulfides,which would prompt a great development for dendrite-blocking and polysulfideinhibiting lithium-metal cells.

关 键 词：Versatile gel polymer electrolyte Multi-scale nanofibers Thermostability Dendrite-blocking and polysulfide-inhibiting Lithium-metal batteries 

分 类 号：TM912[电气工程—电力电子与电力传动] TQ342[化学工程—化纤工业]