掺钇纳米NiO的制备及其超大电容性能研究

Preparation and Supercapacitor Properties of Yttrium Doped NiO

应用化学共沉淀法制备掺Y的纳米N iO.XRD分析表明,Y的添加不改变N iO的晶体结构,但晶粒尺寸有所减小.利用恒流充放电、循环伏安和交流阻抗等测试方法对Y-N iO电极材料在5 mo.lL-1KOH溶液中作电化学性能测试.结果表明,化学掺杂提高了电极的比容量,当N iO与Y2O3的质量比为1∶0.1时,单电极放电比容量可达到363 F.g-1,比纯氧化镍电极提高了2.02倍.交流阻抗测试显示,Y掺杂降低了电解液在电极中的扩散阻力,提高了质子扩散能力,从而表现了更好的电容性能.

Yttrium doped Nano-NiO were synthesized by chemical precipitation method. Characterization and performance of the samples were studied by X-ray diffraction, the results showed that the doping Yttrium did not change the crystal structure of NiO, but the size of crystalline grain was reduced. The electrochemical properties of the electrode materials were measured in the three electrode system. Electrochemical properties of NiO were researched by cyclic voltammetry, constant current charge/discharge and AC impedance methods. It could be seen that the chemical doping improved the specific capacitance and the utilization of active materials. When the weight ratio of NiO with Y2O3 was 1 ： 0. 1, the composite material had the best properties. The maximum discharge specific capacitance was 363F g^-1 in the 5 mol·L^-1 KOH solution. The result of AC impedance showed that the doping could improve the electrochemical reversibility, reduce the resistance of cations transfered between the electrode and electrolyte which made the electrodes show the better capacitive behavior.