氧化镍/镍/石墨烯的制备与电容性能

Preparation and performance of nickel oxide/nickel/graphene composite material as supercapacitor electrodes

通过溶胶凝胶法,以柠檬酸为络合剂制备前驱体,然后在氮气气氛下进行热处理合成氧化镍/镍/石墨烯复合材料。扫描电镜结果显示,产物中氧化镍/镍纳米颗粒分散到石墨烯层与层之间及其表面上。通过循环伏安和恒电流充放电对复合材料的电化学性能进行测试。结果表明,添加2%氧化石墨烯(GO)制备的氧化镍/镍/石墨烯(NiO/Ni/rGO)复合材料具有最佳比电容、倍率性能以及循环性能;在10 mV/s的扫描速率下,所制备的氧化镍/镍/石墨烯复合材料的比电容可达到1 428 F/g;在5 A/g的电流密度下循环1 000次后,比电容仍能达到1 157 F/g。

A novel NiO/Ni/rGO composite were successfully fabricated by calcination in an inert atmosphere (N2) from its precursor prepared by a simple sol-gel method with citric acid as the complexing agent. The results of scanning electron microscopy show that NiO/Ni particles are evenly dispersed on the surface of thermal reduced graphene oxide (rGO) sheets. The electrochemical properties of the composites were investigated by cyclic voltammetry as well as galvanostatic current charge and discharge tests. The research results indicate that NiO/Ni/rGO composites added with 2% graphene oxide (GO) in the precursor can exhibit an excellent electrochemical performance with a specific capacitance of 1 428 F/g at a scanning rate of 10 mV/s, and also retain specific capacity of 1 157 F/g after 1 000 cycles at current density of 5 A/g in a 1 mol/L Na2SO4 aqueous electrolyte.