超细氢氧化亚镍的溶胶凝胶法制备及其准电容特性  

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

作　　者：王晓峰[1] 王大志[1] 梁吉[1] 

机构地区：[1]清华大学机械工程系,北京100084

出　　处：《物理化学学报》2005年第2期117-122,共6页Acta Physico-Chimica Sinica

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200nm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320F·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1.6V,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8.6W·g-1.当以0.88W·g-1功率放电时,电容器能量密度可达20.11W·h·kg-1,当采用3.46W·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11.11W·h·kg-1.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 praticles have a diameter range of 100 similar to 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.

关 键 词：复合型电化学电容器 氢氧化亚镍 碳纳米管 活性炭 

分 类 号：TM53[电气工程—电器]