自支撑NiCo_(2)O_(4)/NF电极的合成及其电化学性能表征

Synthesis of self-supporting NiCo_(2)O_(4)/NF electrode and characterization of its electrochemical performance

以泡沫镍(NF)为自支撑集流体,通过溶剂热法和焙烧处理制备了NiCo_(2)O_(4)/NF自支撑电极,利用XRD、SEM、TEM、XPS、氮气吸脱附对NiCo_(2)O_(4)/NF的化学组成及微观结构进行表征,结果发现,由细小纳米颗粒组成的线状NiCo_(2)O_(4)有序、垂直生长于NF骨架表面,NiCo_(2)O_(4)/NF具有的高比表面积和大量孔结构促进了电解液和电极间的充分接触,NF作为基底有利于提高NiCo_(2)O_(4)的结构稳定性。同时,对NiCo_(2)O_(4)/NF电极进行了电化学测试,结果表明,NiCo_(2)O_(4)/NF在0.5 A/g下的比电容达1 095 F/g, 10 A/g的容量保持率为68.3%,说明其具有良好的倍率性能。此外,经过999次循环,NiCo_(2)O_(4)/NF的比容量为初始比电容的82.3%。

A self-supporting 3D NiCo_(2)O_(4)/NF electrode is synthesized via solvothermal process and calcination treatment with Ni foam(NF)as self-supporting current collector.The chemical composition and microstructure of NiCo_(2)O_(4)/NF are observed by virtue of XRD,SEM,TEM,XPS and nitrogen adsorption-desorption isotherm.It is found that NiCo_(2)O_(4) nanowires composed of small nanoparticles vertically grow on NF skeleton surface in order.The high active specific surface area and numerous pores in NiCo_(2)O_(4)/NF electrode are beneficial for the complete contact between electrolyte and electrode,and NF as substrate improves the structural stability of NiCo_(2)O_(4) nanowires.What is more,the electrochemical performance of NiCo_(2)O_(4)/NF is characterized.NiCo_(2)O_(4)/NF shows a high specific capacitance of 1095 F·g^(-1) at 0.5 A·g^(-1) and a moderate capacitance retention of 68.3%at 10 A·g^(-1) which declares a good rate performance.In addition,the good capacitance retention of about 82.3%is achieved after 999 cycles.