CuO表面修饰锐钛矿TiO_2纳米管阵列及其电化学嵌锂性能

Surface Modification and Electrochemical Lithium Storage Performance of TiO_2-Anatase Nanotube Arrays with CuO

以(CH_2OH)_2、NH4F和HCl为电解液,纯Ti片、CuCl_2和Na NO3为主要原料,联用阳极氧化和水热法制备CuO表面修饰锐钛矿TiO_2纳米管阵列锂离子电池负极材料(CuO/TiO_2)。使用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、能谱仪(EDS)、X射线光电子能谱仪(XPS)和X射线衍射(XRD),研究样品的形貌特征、元素分布、价态和微观物相组成。利用电池充放电测试仪和电化学工作站,探讨材料的电化学嵌锂性能。结果表明,表面修饰后的锐钛矿TiO_2纳米管阵列外侧出现了大量绒毛状纳米CuO,单个绒毛结构的宽度约4 nm,长度约10 nm。在0.3C的电流密度下进行恒电流充放电测试,首次放电容量为550 m Ah·g^(-1),充电容量为490 m Ah·g^(-1)。50次循环后,可逆电流容量仍保持在320 m Ah·g^(-1),具有良好的循环稳定性和电化学特性。

Anodic oxidation and hydrothermal method were jointly used to prepare CuO/TiO2 negative material which was synthesized from ethylene glycol,ammonium fluoride,hydrochloric acid,cupric chloride and sodium nitrate.Morphology,element distribution,valence state,microcosmic phase composition of the samples were investigated by scanning electron microscopy(SEM),transmission electron microscopy(TEM),energy dispersive spectroscopy(EDS),X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD).Furthermore,the electrochemical lithium insertion properties of CuO/TiO2 were tested by the use of battery charge and discharge testing system and electrochemical workstation.The results show that there are particulates arrange the surface of the anatase TiO2 nanotube.The nanometer size was 4 nmx10 nm.The as prepared CuO/TiO2 displays plummy electric properties of initial discharge and charge capacities of 550 and 490 mAh'g-1 at the rate of 0.3C.respectively.After 50 cycles the reserve capacities is 320 mAh'g-1.