GS-SSCNTs-MnNPs复合材料的制备与锂离子电池负极性能研究

The Preparation of Graphene/Super Short Carbon Nanotubes/MnO_2 Nanocomposites as and Anode Performance of Lithium-Ion Batteries

在超声环境下,采用强氧化法将多壁碳纳米管(MWCNTs)切割成长径比小于5的超短碳纳米管(SSCNTs),通过简单的湿化学法将其与MnO_x纳米颗粒(MnxNPs)植入还原性氧化石墨烯片层中,热处理后,形成GS-SSCNTs-MnNPs纳米复合材料.通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X-射线衍射(XRD)等制备材料的形貌结构,采用循环伏安和恒流充放电研究其锂离子电池负极性能.结果表明:GS-SSCNTs-MnNPs纳米复合材料在180 m A·g^(-1)电流密度下具有高达1 100 m A·h·g^(-1)的可逆容量,且表现出优异的功率和循环稳定性能,循环100圈之后,仍具有高达837 m A·h·g^(-1)的可逆容量(1 440 m A·g^(-1)).

Multiwalled carbon nanotubes( MWCNTs) are cut into super short carbon nanotubes( SSCNTs) with aspect ratio of less than 5 by using strong oxidation method under ultrasonic environment. RGO-SSCNT-MnO_2 nanocomposites are designed by a simple wet chemical method and heat treatment,which makes SSCNTs and Mn Oxnanoparticles( MnxNPs) into RGO layers. The morphology of nanocomposites is investigated by scanning electron microscopy( SEM),transmission electron microscopy( TEM) and X-ray diffraction( XRD). The performanceof anode is studied by cyclic voltammetry and constant current charge/dischargefor lithium-ion batteries. The results show that the composites have a reversible capacity of 1 100 m A ·h ·g^(-1)in the current density of 180 m A ·g^(-1),and exhibite excellent power and cycling stabilities. After 100 cycles in current density of 1 440 m A·h· g^(-1),the compositesstill have a reversible capacity of 837 m A·h·g^(-1).