高比容纳米Ni（OH）_2的制备及其电化学电容性能

摘要

以草酸和乙酸镍为原料,通过低温固相法合成前驱体（NiC2O4.2H2O）粉末。用此前驱体粉末与固态NaOH混合并充分研磨制得纳米Ni（OH）2粉末。经SEM、XRD测试表明,制得的纳米Ni（OH）2粉末是平均粒径约为12nm的β-Ni（OH）2。用循环伏安法、恒流充放电测试和交流阻抗谱研究Ni（OH）2电极的电化学电容特性。结果表明在电流密度为1A.g-1时,其比电容高达2271F.g-1,且经多次循环后表现出较好的循环稳定性能。%Ni （OH）2 nano-powders were prepared using NiC2O4·2H2O as precursor, which was synthesized by low-temperature solid-state reaction of oxalic acid and nickel acetate. Scanning electron microscopy （SEM） and X-ray diffractometry （XRD） results show that the as-prepared Ni（OH）2 powder is β- Ni（OH）2 with an average diameter of 12 nm. Electrochemical capacitance behavior of the Ni（OH）2 electrode was investigated by cyclic voltammetry, galvanostatic charge-discharge test and electrochemical impedance spectroscopy. Ni（OH）2 electrode displays a specific capacitance of 2271 F.g-1 at a current density of 1 A-g 1 and it has good steady cycling performance.