热处理温度及掺杂对氧化镍电极赝电容器特性的影响

EFFECT OF ANNEALING TEMPERATURE AND DOPING ON CHARACTERISTICS OF PSEUDOCAPACITORS UTILIZING NICKEL OXIDE ELECTRODES

应用电化学阴极沉积法在Ni基片上制得Ni(OH) 2 膜 ,经热处理得到NiO膜 .研究了热处理温度、钴掺杂对NiO膜电极赝电容性能的影响 .结果发现 :在 2 5 0～ 5 0 0℃ ,随着热处理温度的升高 ,NiO膜电极比电容量逐渐减小 ;钴掺杂使比电容量显著增大 .以掺钴的NiO膜为电极 ,以 1mol/L的KOH水溶液为电解质溶液 ,所得电容器的比电容量可达

Films of nickel hydroxide were electrochemically precipitated on nickel substrate and then annealed in air to obtain films of nickel oxide. Thermogravimetric analysis indicates that nickel hydroxide begins to turn into nickel oxide when the annealing temperature reaches 230 ℃. X_ray diffractometry identifies that there is only a single nickel oxide phase in the annealed films. Cyclic voltammetry and charge/discharge test were employed to determine the specific capacitance. The effect of annealing temperature of Ni(OH) 2 and doped cobalt on the properties of pseudocapacitance of nickel oxide electrodes are discussed in this paper. The results show that specific capacitance decreases when the annealing temperature increases from 250 ℃ to 500 ℃, because the size of crystallite of nickel oxide is enlarged and the amount of crystallite boundary is reduced. The specific capacitance is enlarged when cobalt is doped into nickel oxide as a result of the increase of lattice defects of nickel oxide.