摘 要：采用化学水热法制得纯相Co(OH)2和活性炭改性Co(OH)2（C-Co(OH)2）复合材料用于超级电容器材料。采用X射线衍射(XRD)和扫描电镜(SEM)表征了产物的结构和形貌，结果表明，150℃ 6h的水热反应条件下获得的Co(OH)2为分散度高、形貌规则的六边形薄片状；六方形的Co(OH)2薄片均匀分散在C-Co(OH)2复合材料中。采用循环伏安、恒流充放电、交流阻抗等电化学方法考察其电化学性能。结果发现C-Co(OH)2电极比Co(OH)2电极具有更加优异的电化学性能：循环伏安分析表明， C-Co(OH)2电极在0~0.6V（VS.SCE)，表现出良好的矩形特征；在0~0.6v充放电电位区间、0.1A/g电流密度下研究其充放电性能，发现当C与Co的质量比为16：1时电容器的充放电性能良好，比容量和储能密度均达到最大，分别为151.33F·g-1，储能密度为0.0174Wh·kg-1，在充放电100次后，C-Co(OH)2的比容量没有衰减，说明产物具有较好的电化学稳定性，有望成为超级电容器的电极材料。54283

毕业论文关键词：超级电容器，Co(OH)2，活性炭，循环伏安，充放电，比电容

Abstract：Co(OH)2 and Activated carbon (C) modified Co(OH)2 (C-Co(OH)2) used as electrode materials for supercapacitors were synthesized by hydro-thermal method under 150oC for 6h. The structure of the products was characterized using X-ray diffraction (XRD) and scanning electron microscope (SEM). It was found that Co(OH)2 presented as Hexagonal sheet-like structure with high dispersibility and it was uniformly dispered in active carbon. The electrochemical performances of the obtained products are investigated by cyclic voltammetry(CV), constant current charge/discharge and electrochemical impedance spectroscopy (ESR) techniques. The tests found that C-Co(OH)2 presents better electrochemical property than that of pure Co(OH)2.Based on Cyclic voltammograms (vs.SCE), the working voltage for C-Co(OH)2 composites with ideal capacitor behavior were 0V-0.6 V respectively in 0.5mol·L- 1 Na2SO4. Charge and discharge behavior of the products between 0~0.6Vunder different current densities were studied, the results show that the optimum current density is 0.1 A • g-1. Under this condition, the specific capacity and energy density reached the maximum. The specific capacity was 151.33F • g-1, energy density is 0.0174Wh • kg-1, respectively. After the 100 charge and discharge cycles, capacity of C-Co(OH)2 almost maintain the same as original, indicating  C-Co(OH)2 has better electrochemical stability, which is expected to be used as the supercapacitor electrode material.

Keywords: Supercapacito, C-Co(OH)2, Cyclic voltamper, Specific capacitance

目   录

1.  前言 4

1.1  超级电容器的简介 4

1.2  超级电容器的原理和分类 4

1.3  超级电容器的特点及应用 4

1.4 超级电容器的电极材料 4

2  实验部分 5

2.1  仪器和试剂 5

2.2  Co(OH)2与C-Co(OH)2复合材料的制备 5

2.3  材料表征 5

2.3.1  粉末X射线衍射 6

2.3.2  扫射电镜形貌分析 6

2.4  电极材料的制备 6

2.5  电化学测试方法 6

3  结果与讨论 6

3.1  XRD分析 6

3.2  扫射电镜图形