中空Cu7S4纳米立方的制备及其电化学电容性能

Cubic Nano Cu_7S_4 with Hollow Structures:Their Preparation and Electrochemical Capacitance Performance

本文以化学沉淀法制备出立方体Cu_2O,以Cu_2O为模板用水热离子交换法制备出纳米Cu_7S_4。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Cu_7S_4进行测试,结果显示Cu_7S_4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Cu_7S_4的电化学性能。测试结果表明,当电流密度为1A·g^(-1)时,Cu_7S_4的比电容为275F·g^(-1)。在电流密度为4A·g^(-1)时,Cu_7S_4循环1000次仍能保留94.8%的比电容,展示出良好的循环性能。

Cu2O was synthesized by chemical precipitation, then nano Cu7S4 was synthesized via a hydrothermal ion-exchange method using the Cu20 as the template. Characterizations of the product using X- ray 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, galvanostatie 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.