多壁碳纳米管的改性

CVD 法不同条件下制备的多壁碳纳米管的Fenton 氧化改性

李伟　成荣明＊　徐学诚　陈奕卫　孙明礼　何为凡

(华东师范大学纳米功能材料和器件应用研究中心　上海　200062)

李伟　男,24岁,硕士生,现从事碳纳米管的改性研究。　＊联系人,E -mail :ys 02122048@student .ecnu .edu .cn

上海纳米科技专项基金资助项目(0252nm011)2004-08-27收稿,2005-01-31接受摘　要　碳纳米管经焙烧和稀硝酸纯化处理后,在相同的实验条件下,采用Fenton 试剂产生的·OH

分别对C VD 法合成的两种制备条件不同的多壁碳纳米管进行氧化改性处理。红外光谱(FT -IR )表明,改

性后的两种碳管结构中都引入了羟基、羰基和羧基等含氧官能团。此外,由于制备条件不同,导致它们

的石墨化程度、缺陷含量和抗氧化能力等性质也不同,因此CVD 法制备条件能够对碳管Fenton 氧化改

性结果产生重要影响。机理分析表明,这些含氧官能团可以看作是具有强亲电性和强氧化性的·OH 对

碳管上缺陷位置和不饱和键进行攻击的结果。

关键词　多壁碳纳米管　Fenton 试剂　·OH 机理

Fenton Oxidation Modification of Multi -walled Carbon Nanotubes Prepared

in Different Conditions by C VD Method

Li Wei ,Cheng Rongming ＊

,Xu Xuecheng ,Chen Yiwei ,Sun Mingli ,He Weifan

(Center of Functional Nanomaterials and Devices ,East China Normal Universit y ,Shanghai 200062)

A bstract After purification pretreatment by heating in air and in dilute HNO 3,in the same experimental

conditions two kinds of multi -walled carbon nanotubes (MWNTs )were treated with Fenton 's reagents ,which were

s ynthesized in different preparation conditions by chemical vapor deposition (CVD )method .The results of FT -IR

spectra indicated that the oxygen -containing functional groups such as hydroxyl groups ,carbon y l groups and carboxyl

groups could be brought into two kinds of MWNTs after Fenton oxidation modification treatment .In addition ,the

properties such as graphitization degree ,defects ′content and antioxidation ability are also different for the different

preparation conditions .So the preparation conditions of MWNTs could affect intens ively the results of Fenton oxidation

modification .Finally ,we discussed the possible mechanisms of reaction between hydroxyl radical and MWNTs by FT -

IR spectral changes before and after Fenton modification treatments were discussed .The possible mechanisms

indicated that the existence of oxygen -containing functional groups could be viewed as outcome of attacks of h ydroxyl

radical (·OH )with both the properties of oxidizabilit y and electrophilic addition on defect sites and unsaturated bonds

in the MWNTs sample .

Key words Multi -walled carbon nanotubes (MWNTs ),Fenton 's reagents ,Hydroxyl radical ,Mechanis ms 1991年日本科学家Iijima [1]

用高分辩透射电镜(HRTE M )发现了纳米尺寸的多壁碳纳米管(multi -walled car bon nanotubes ,MWNTs )。由于其独特的结构和物理化学性质,在许多新领域都可望得到应用,如在纳米电子器件[2]、超强度复合材料[3]等领域都显示了巨大的潜力。目前碳纳米管的制备方法主要有三种:电弧法(arc discharge ,AD )、激光蚀刻法(laser alblation ,LA )和化学气相沉积法(c hemical vapor deposition ,CVD )。其中CVD 法产量大,成本低,易于实现工业化大批量连续生产,

·618·化学通报　2005年第8期 http : www .hxtb .org DOI :10.14159/j .cn ki .0441-3776.2005.08.009