基于碳点调控氧化锌纳米阵列构建三维集流体用于高效锂金属负极  

Carbon dot modified ZnO nanoarrays to construct 3Dcurrent collectors for lithium metal anodes

作　　者：王卓 杨国夺 夏宁 杨柏[2] 孙海珠 赵亮 WANG Zhuo;YANG Guo-duo;XIA Ning;YANG Bai;SUN Hai-zhu;ZHAO Liang(College of Chemistry,National&Local United Engineering Laboratory for Power Batteries,Northeast Normal University,Changchun 130024,China;State Key Laboratory of Supramolecular Structure and Materials,College of Chemistry,Jilin University,Changchun 130012,China)

机构地区：[1]东北师范大学化学学院,动力电池国家地方联合工程实验室,吉林长春130024 [2]吉林大学化学学院,超分子结构与材料国家重点实验室,吉林长春130012

出　　处：《分子科学学报》2023年第5期446-452,共7页Journal of Molecular Science

基　　金：国家自然科学基金资助项目(22275030,22035001);吉林省教育厅和中央高校基本科研业务费科技成果转化专项资金资助项目(CGZH202203).

摘　　要：本文结合原位生长和热处理法成功制备出了ZnO@CD@CC材料,并将其应用于锂金属负极基底材料,用于诱导锂金属均匀沉积.本工作使用旧实验服棉布和常温合成方法降低了实验成本;引入碳点能够有效调控ZnO纳米阵列形貌,负载形貌均一的亲锂ZnO使整个碳纤维上亲锂位点更均匀,有助于降低锂的成核过电势,诱导Li+均匀沉积.电化学性能测试结果显示,ZnO@CD@CC在面积容量为1mAh·cm^(-2)和电流密度为3mA·cm^(-2)的条件下能够稳定循环超过500h(电压滞后仅为50.8mV).Lithium metal anode(LMA)is considered to be the ideal anode materials for the next generation of lithium batteries due to its ultra-high theoretical capacity(3860 mAh·g^(-1))and lowest electrochemical potential(-3.04Vrelative to the standard hydrogen electrode).However,it is limited by the growth of lithium dendrites and volume change,which seriously hinder its practical application.Constructing 3Dcurrent collector,optimizing electrolyte composition,and designing artificial protective layer can mitigate the above problems.Among them,3Dcarbon-based current collector with high specific area can reduce the local current density and inhibit the growth of dendrites.3D skeleton structure can accommodate lithium metal and limit the infinite volume expansion of LMA.However,the lithiophobic of the carbon is not conducive to achieving uniform lithium deposition.Therefore,modification of lithiophilic materials on 3Dcarbon-based substrates is a simple and effective method for operation.In this work,a CC(carbon cloths)coating ZnO nanoarrays modified with carbon dots(CDs)current collector(ZnO@CD@CC)was prepared by combining in-situ growth and annealing methods as the host of lithium metal.The waste cotton cloth and room temperature conditions ensure low-cost experiments.The introduction of CDs can effectively regulate the morphology of ZnO nanoarrays.Homogeneous ZnO contributes to the uniform distribution of lithophilic sites throughout CC,which reduce the nucleation overpotential of lithium and induce uniform deposition of Li^(+).The electrochemical performance test results show that ZnO@CD@CC run stably for more than 500h(voltage lag is only 50.8mV)with an area capacity of 1mAh·cm^(-2)at 3mA·cm^(-2).

关 键 词：锂金属阳极 碳点 亲锂改性 ZNO 3D集流器 

分 类 号：O646[理学—物理化学]