化学学报 ›› 2004, Vol. 62 ›› Issue (15): 1447-1450. 上一篇    下一篇

研究简报

吸附聚丙烯酸对纳米碳管表面特征影响的研究

崔举庆1, 侯庆锋1, 陆现彩2, 何其慧1, 刘显东2, 沈健1,3, 胡柏星1   

  1. 1. 南京大学表面和界面化学工程技术研究中心, 南京, 210093;
    2. 南京大学地球科学系, 内生矿床成矿机制研究国家重点实验室, 南京, 210093;
    3. 南京师范大学化学与环境科学学院, 南京, 210097
  • 投稿日期:2003-11-03 修回日期:2004-02-27 发布日期:2014-02-17
  • 通讯作者: 胡柏星,E-mail:juqing78@yahoo.com.cn E-mail:juqing78@yahoo.com.cn
  • 基金资助:
    南京大学分析测试基金(No.DK3-7)资助项目.

Investigation on the Surface Properties of the Carbon Nanotubes before and after the Adsorption of Polyacrylic Acid

CUI Ju-Qing1, HOU Qing-Feng1, LU Xian-Cai2, HE Qi-Hui1, LIU Xian-Dong2, SHEN Jian1,3, HU Bai-Xing1   

  1. 1. Research Center of Surface and Interface Chemical Engineering Technology, Nanjing University, Nanjing 210093;
    2. State Key Laboratory for Mineral Deposit Research, Department of Earth Sciences, Nanjing University, Nanjing 210093;
    3. College of Chemistry and Environment Science, Nanjing Normal University, Nanjing 210097
  • Received:2003-11-03 Revised:2004-02-27 Published:2014-02-17

利用低温氮气吸附法系统研究了吸附聚丙烯酸(PAA)的量对纳米碳管表面特征的影响.分析结果表明:当PAA吸附量增加到268.98 mg·g-1时,纳米碳管的比表面积下降了46.97%;虽然吸附PAA后的纳米碳管在1.8 nm以上的孔径分布特征基本上与原样一致,但孔容减少,这部分孔对比表面的贡献明显降低,同时出现1.8 nm以下的孔;通过氮气吸附等温线利用热力学方法计算的纳米碳管的表面分维值(surface fractal dimension)dSF由原样的2.54下降至吸附后的2.48,表明吸附PAA分子能够降低纳米碳管的粗糙度.这些说明堵孔效应和屏蔽效应是纳米碳管表面特征改变的主要因素,这一研究对纳米碳管在吸附、催化等方面的应用有着非常重要的意义.

关键词: 纳米碳管, 聚丙烯酸, 吸附, 比表面积, 孔径分布, 表面分维

In this work, the variations in surface properties of the carbon nanotubes due to the adsorption of polyacrylic acid (PAA) was investigated based on the nitrogen adsorption isotherms.It is indicated that the adsorption of PAA greatly influences the original surface properties of the carbon nanotubes.A remarkable decrease in BET specific surface area (SBET) was found while the adsorption amount of PAA increased.And the patterns of pore size distribution (PSD) of the treated carbon nanotubes are similar to those of the original ones, especially in the range of 1.8~4.4 nm, however, the pore volume decreases as the adsorption of PAA increases and a new type of pore with the width less than 1.8 nm appears.The surface fractal dimension (dSF) calculated from the nitrogen adsorption isotherms employing the thermodynamic methods shows that the adsorbed PAA can lower the surface roughness of carbon nanotubes.All the observed variation in SBET, PSD and dSF could be attributed to the pore blocking effect and surface screening effect of the adsorbed PAA.This study will facilitate the understanding and application in the field of adsorbent and catalyst.

Key words: carbon nanotube, PAA, adsorption, specific surface area, pore size distribution, surface fractal dimension