物理化学学报 >> 2009, Vol. 25 >> Issue (05): 987-993.doi: 10.3866/PKU.WHXB20090410

研究论文 上一篇    下一篇

低热固相法制备纳米MnO2/CNT超电容复合电极的循环稳定性

胡洁 袁安保 王玉芹 王秀玲   

  1. 上海大学理学院化学系, 上海 200444
  • 收稿日期:2008-11-04 修回日期:2008-12-31 发布日期:2009-05-04
  • 通讯作者: 袁安保 E-mail:abyuan@shu.edu.cn

Improved Cyclability of Nano-MnO2/CNT Composite Supercapacitor Electrode Derived fromRoom-Temperature Solid Reaction

HU Jie, YUAN An-Bao, WANG Yu-Qin, WANG Xiu-Ling   

  1. Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, P. R. China
  • Received:2008-11-04 Revised:2008-12-31 Published:2009-05-04
  • Contact: YUAN An-Bao E-mail:abyuan@shu.edu.cn

摘要:

为了改善纳米MnO2超级电容器电极的充放电循环稳定性, 以Mn(OAc)2·4H2O、NH4HCO3和碳纳米管(CNT)为原料, 采用低热固相反应得到前驱体, 再经焙烧和酸处理, 制备了一系列CNT含量不同的纳米MnO2/CNT复合电极材料, 并用X射线衍射(XRD)、透射电镜(TEM)和Brunauer-Emmett-Teller(BET)比表面积测定方法对其进行了表征援XRD分析结果表明, 复合材料中的MnO2为纳米酌-MnO2援研究了复合电极在1 mol·L-1 LiOH电解质中的电化学性能, 并与不含CNT的纯纳米MnO2电极进行了比较援结果表明, 含CNTs为10%(w, 质量分数, 下同) 和20%的MnO2/CNT复合电极的循环稳定性远优于纯纳米MnO2电极的循环稳定性, 其中含10% CNTs的MnO2/CNT复合电极不仅具有良好的循环稳定性, 而且在1000 mA·g-1高倍率充放电条件下仍具有200 F·g-1的高比电容.

关键词: 纳米MnO2/CNT复合电极, 超电容性能, 循环稳定性, 低热固相法, LiOH电解质

Abstract:

To improve the charge/discharge cycle stability of a nanostructured manganese dioxide electrode for supercapacitor applications, a series of nano-MnO2/carbon nanotube (CNT) hybrid electrode materials with different mass fractions of CNTs were prepared. The materials were prepared using a room-temperature solid-grinding reaction betweenMn(OAc)2·4H2Oand NH4HCO3 in the presence of CNTs to obtain a precursor. This was followed by calcination and an acid-treatment process and the products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) surface analysis. XRD results indicated that the MnO2 in the composites was nanostructured 酌-MnO2. Electrochemical performance of the MnO2/CNT composite electrodes in 1 mol·L-1 LiOH alkaline aqueous electrolyte was studied and compared to a pure nano-MnO2 electrode without CNTs. The MnO2/CNT composite electrodes with 10% or 20% (w, mass fraction) CNTs showed far superior cycle stability than the pure MnO2 electrode. The MnO2/CNT composite electrode with 10% CNTs exhibited good cycling stability and also a high specific capacitance of 200 F·g-1 at a high charge/discharge current rate of 1000 mA·g-1.

Key words: Nanostructured manganese dioxide/carbon nanotube composite, Super capacitive property, Cyclability, Room-temperature solid-grinding reaction, Lithium hydroxide electrolyte

MSC2000: 

  • O646