物理化学学报 >> 2005, Vol. 21 >> Issue (02): 117-122.doi: 10.3866/PKU.WHXB20050202

研究论文 上一篇    下一篇

超细氢氧化亚镍的溶胶凝胶法制备及其准电容特性

王晓峰; 王大志; 梁吉   

  1. 清华大学机械工程系,北京 100084
  • 收稿日期:2004-06-24 修回日期:2004-08-25 发布日期:2005-02-15
  • 通讯作者: 王晓峰 E-mail:xfw@mail.tsinghua.edu.cn

Pseudo-capacitance of Ultrafine Nickel Hydroxide Prepared by Sol-gel Method

WANG Xiao-Feng; WANG Da-Zhi; LIANG Ji   

  1. Department of Mechanical Engineering, Tsinghua University, Beijing 100084
  • Received:2004-06-24 Revised:2004-08-25 Published:2005-02-15
  • Contact: WANG Xiao-Feng E-mail:xfw@mail.tsinghua.edu.cn

摘要: 以聚乙二醇为抑制剂,采用溶胶凝胶法制备了粒径小于200 nm且具有链珠状特殊形态的超细氢氧化亚镍电极材料.伏安特性测试和电化学阻抗测试表明在氢氧化亚镍中掺加适量碳纳米管可以显著改善电极材料的容量特性和阻抗特性,其中碳纳米管质量分数为20%的复合电极其比电容量可以达到320 F•g-1.采用复合电极作为正极,活性炭电极作为负极组成的复合型电化学电容器最大工作电压可以达到1.6 V,具有良好的容量特性和大电流放电特性.恒流充放电测试证明复合型电化学电容器具有高能量密度及高功率放电特性,电容器的峰值功率密度为8.6 W•g-1.当以0.88 W•g-1功率放电时,电容器能量密度可达20.11 W•h•kg-1, 当采用3.46 W•g-1的高功率进行放电时,复合型电容器的能量密度仍然能够达到11.11 W•h•kg-1.

关键词: 复合型电化学电容器, 氢氧化亚镍, 碳纳米管, 活性炭

Abstract: A new sol-gel process for the preparation of ultrafine nickel hydroxide electrode materials was developed. The particle size and configuration of the nickel hydroxide product can be controlled with polyethylene glycol. The hydroxide particles have a diameter range of 100~200 nm and take on an unique chain-bead like configuration. The composite electrodes consisting of carbon nanotubes and Ni(OH)2 were developed by mixing the hydroxide and carbon nanotubes together in varous ratios. A maximum capacitance of 320 F•g-1 was obtained for the composite electrode containing 20% carbon nanotubes compared with that of activated carbon(184 F•g-1). The performance of a newly designed combined electrochemical capacitor was evaluated. The capacitor was prepared by using nickel hydroxide/carbon nanotubes composite as a positive electrode and activated carbon as a negative electrode. Values for the specific energy and maximum specific power of 20.11 W•h•kg-1 and 8.6 W•g-1,respectively,were demonstrated for a cell voltage between 0 and 1.6 V. By using the modified anode of a Ni(OH)2/carbon nanotubes composite electrode, the combined supercapacitor exhibited high energy density and stable power characteristics.

Key words: Combined supercapacitor, Nickel hydroxide, Carbon nanotubes, Activated carbon