Preparation and Properties of Nanocrystalline Nickel by Pulse Electrodeposition on Glassy Carbon

由于纳米晶体镍具有电催化甲醇的活性,本文采用双脉冲法在玻碳表面上电沉积制备了纳米晶体镍，并分析了脉冲条件对其晶粒尺寸的影响。电沉积的溶液组成为300 g·L-1 NiSO4·6H2O，45 g·L-1 NiCl2·6H2O，40 g·L-1 H3BO3，5 g·L-1 C7H5NO3S，0.05 g·L-1 C12H25NaO4S，最优的脉冲工艺参数是脉冲平均电流密度为100 mA·cm-2、脉冲占空比为30%,脉冲频率为100 Hz, pH为1.5、温度为55 oC。利用XRD、TEM、循环伏安以及电化学阻抗分析了纳米晶体镍的晶粒尺寸、结构及性能。制备的电沉积层致密均匀，为典型的面心立方结构，晶体镍的平均粒径在18 nm左右，玻碳材料表面上通过电沉积得到的纳米晶体镍在碱性环境下对甲醇具有良好的电催化活性。Nanocrystalline nickel exhibits electrocatalytic activity for methanol. In this work, nanocrystalline nickel coating has been obtained by using the double pulse method on glassy carbon materials surface. The influence of pulse conditions on the grain size of nanocrystalline nicke was studied. The concentrations and compositions of the plating bath were  300 g·L-1 NiSO4·6H2O，45 g·L-1 NiCl2·6H2O，40 g·L-1 H3BO3，5 g·L-1 C7H5NO3S，and 0.05 g·L-1 C12H25NaO4S. The optimal pulse process parameters including the average pulse current density of 100 mA·cm-2, pulse duty ratio of 30%, pulse frequency of 1000 Hz, pH of 1.5, and treatment temperature of 55 ℃ were determined. The grain size, surface morphology, structure and electrochemical properties of the prepared nanocrystalline nickel were investigated by XRD, TEM, cyclic voltammetry and electrochemical impedance spectroscop. Accordingly, the dense, smooth, and continuous uniform electrodeposition layer with the typical face-centered cubic structure was developed. The average size of the nanocrystalline nickel was about 18 nm. Cyclic voltammetric and electrochemical impedance spectroscopic results showed that the nanocrystalline nickel electrodeposited on the glassy carbon surface had good electrocatalytic activity for methanol in an alkaline environment.作者联系地址：燕山大学环境与化学工程学院，秦皇岛 066004Author's Address: College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China通讯作者E-mail：yshxue@ysu.edu.cn