Polydopamine-assisted in-situ formation of dense MOF layer on polyolefin separator for synergistic enhancement of lithium-sulfur battery  

作　　者：Xiuxiu Wu Cheng Zhou Chenxu Dong Chunli Shen Binbin Shuai Cheng Li Yan Li Qinyou An Xu Xu Liqiang Mai 

机构地区：[1]State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,China [2]International School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China

出　　处：《Nano Research》2022年第9期8048-8055,共8页纳米研究（英文版）

基　　金：the Ministry of Science and Technology of the People’s Republic of China(No.2017YFE0127600);the National Natural Science Foundation of China(No.51702247);the Fundamental Research Funds for the Central Universities(No.WUT:2020III023,2020III050,2021IVA123,2021III009);Hainan Provincial Joint Project of Sanya Yazhou Bay Science and Technology City(No.520LH056);Sanya Science and Education Innovation Park of Wuhan University of Technology(No.2020KF0021);the State Key Laboratory of Advanced Technology for Materials Synthesis and Processing(WUT:2021-ZD-1).

摘　　要：The separator is of great significance to alleviate the shuttle effect and dendrite growth of lithium-sulfur batteries.However,most of the current commercial separators cannot meet these requirements well.In this work,a dense metal-organic-framework(MOF)modification layer is in-situ prepared by the assistant of polydopamine on the polypropylene separators.Due to the unique structure and synergistic effect of polydopamine(PDA)and zeolitic imidazolate framework-8(ZIF-8),the functional separator can not only trap the polysulfides effectively but also promote the transport of lithium ions.As a result,the battery assembled with the functional separator exhibits excellent cycle stability.The capacity remains 711 mAh·g^(−1)after 500 cycles at 2 C,and the capacity decay rate is as low as 0.013%per cycle.The symmetrical battery is cycled for 1,000 h at 2 mA·cm^(−2)(2 mAh·cm^(−2))with the plating/stripping overpotential of 20 mV.At the same time,the modification separator shows a higher lithium ion transference number(0.88),better thermal stability and electrolyte wettability than the unmodified separator.

关 键 词：metal-organic frameworks in-situ growth POLYSULFIDES shuttle effect gradient distribution 

分 类 号：TM912[电气工程—电力电子与电力传动]