水热法制备花状NiCo_(2)O_(4)及其电化学性能研究

Preparation of flowerlike NiCo_(2)O_(4) by hydrothermal method and study on its electrochemical properties

以氯化镍、氯化钴为原料,采用水热法和后续煅烧处理过程制备纳米片组装的3D类花状NiCo_(2)O_(4)。利用XRD、SEM等手段对合成的样品进行物相组成、形貌结构表征,并利用电化学工作站对其进行循环伏安、恒直流充放电和交流阻抗等性能测试。结果表明,制备出的3D花状结构NiCo_(2)O_(4)由多个纳米片组装而成,各单一纳米片的厚度为40~70 nm,并且纳米片上分布着微孔,可以增大电极与电解液的接触面积。NiCo_(2)O_(4)电极材料在电流密度1 A/g的条件下的比电容为508 F/g;在电流密度8 A/g的条件下经过3000次循环后,其比电容保持率为98.5%,表明花状结构表现出高比电容以及良好的循环稳定性。

3D flower-like NiCo_(2)O_(4) is assembled by nanometer sheets that are prepared by hydrothermal method and subsequent calcination process with nickel chloride and cobalt chloride as raw material.XRD,SEM and other means are employed to characterize the phase composition,morphology and structure of the synthesized samples,and electrochemical workstation is used to test the cyclic voltammetry,constant DC charge and discharge,and AC impedance.The results show that the 3D flower-like NiCo_(2)O_(4) is composed of several nanometer sheets,each sheet has a thickness of 40-70 nm and mesoporous are distributed on each sheet,which can increase the contact area between electrode and electrolyte.The specific capacitance of the NiCo_(2)O_(4) electrode material prepared is 508 F·g^(-1) under a current density of 1 A·g^(-1),and the specific capacitance retention rate is 98.5% after 3000 cycles under a current density of 8 A·g^(-1),indicating a high specific capacitance and good cycling stability.