| Super-capacitor is a new kind of energy storage devices with remarkable advantages. Electrode material is an important factor that affects the ECs performances, among these, Ni(OH)2 appears to be a promising material. Ni(OH)2 was prepared by electrodeposit method, and doped with Co,Fe,La and Ce in our work. We planned to gain Ni(OH)2 electrode material with high specific surface area, excellent electrochemical performance, and high specific capacitance.The effect of electrodeposit parameters on the structure and electrochemical characteristics of Ni(OH)2 was studied using different experimental method, such as orthogonal experiment, single factor experiment and contrast analysis. The structure and appearance of Ni(OH)2 were characterized using various techniques such as scanning electron microscopy(SEM) and X-ray diffraction(XRD). The electrochemical performance of Ni(OH)2 was discussed using kinds of measurements such as cyclic voltammetry and constant charging/discharging testing method.The optimum Ni(OH)2 electrodeposit parameters were as the following:C(nickel nitrate)=0.5 mol·L-1, t=2 h,i=10 mA·cm-2,the reactive temperature is 30℃,V(ethanol):V(H2O)=1:1. The prepared Ni(OH)2 exhibited relatively lesser granularity, high specific surface area, eminent capacitive characteristics and excellent cycle life, the specific capacitance value was 550 F·g-1 at a discharging current of 5 mA. The structure of Ni(OH)2 prepared isβ-Ni(OH)2 by means of XRD.The super capacitance influences ofβ-Ni(OH)2 doped with other elements were also studied. The polarization of Lanthanum dopedβ-Ni(OH)2 was increased, it is advantageous to form particular films. Lanthanum existed in the crystal lattice of nickel hydroxide as ions. Nickel hydroxide electrode existed preferable capacitive characteristics and power performance after doped La,Ce,Co,Fe. With the increase of discharging current, specific capacitance appreciably decreased, and the performance of discharging at high current is also excellent.The corresponding grain size ofβ-Ni(OH)2 and La,Ce,Co,Fe dopedβ-Ni(OH)2 are respectively 15, 8, 14, 13, 10 nm calculated by Scherrer formula. Dopedβ-Ni(OH)2 electrode had better capacitive characteristics.
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