Supercapacitor characteristic of La‐doped Ni(OH) ₂ prepared by electrode‐position

Abstract

Abstract Samples of lanthanum‐doped nickel hydroxide were prepared by electrodeposition method. The structure and electrochemical properties of the samples were studied by X‐ray diffraction and a home‐made open three‐electrode cell system, respectively. The results show that the deposition process of Ni(OH) 2 and La(OH) 3 is mainly controlled by electrochemical polarization, which makes it easy to form uniform fine crystals. In addition, La(OH) 3 is not a separate phase and lanthanum ions are doped into Ni(OH) 2 crystal lattices. When V (0.5 mol/L Ni(NO 3 ) 2 )/ V (0.25 mol/L La(NO 3 ) 3 ) was 9:1, the lanthanum‐doped nickel hydroxide reached the highest discharge capability of 840 F/g with a good cyclic reversibility. The capability still retains 670 F/g when the discharge current reaches 1000 mA/g.