中空Cu7S4纳米立方的制备及其电化学电容性能

摘要

Cu2O was synthesized by chemical precipitation,then nano Cu7S4 was synthesized via a hydrothermal ion-exchange method using the Cu2O as the template.Characterizations of the product using Xray diffraction (XRD),scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that the Cu7S4 has a hollow cubic structure,with an average size of ～ 550nm.Electrochemical performance of the Cu7S4 was investigated by cyclic voltammetry,galvanostatic charge-discharge,electrochemical impedance and cycle stability test with a three-electrode system.The test results show that the specific capacitance of the material is 275F· g-1 at a current density of 1A· g-1.At 4 A· g-1,it can retain 94.8 ％ of the specific capacitance after 1000 cycles,showing good cycling stability.%本文以化学沉淀法制备出立方体Cu2O,以Cu2O为模板用水热离子交换法制备出纳米Cu7S4.利用X-射线衍射仪(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)对Cu7S4进行测试,结果显示Cu7S4具有中空立方体结构,平均尺寸在550nm左右.使用三电极体系,采用循环伏安法、恒流充放电、电化学阻抗谱和循环稳定性分析研究了Cu7S4的电化学性能.测试结果表明,当电流密度为1A·g-1时,Cu7S4的比电容为275F·g-1.在电流密度为4A·g-1时,Cu7 S4循环1000次仍能保留94.8％的比电容,展示出良好的循环性能.