【作者】 郭敏；

【导师】 杨全红；

【作者基本信息】 天津大学 ， 应用化学， 2009， 硕士

【摘要】 碳纳米管作为一种准一维纳米材料,因具有优异的光学、电学、力学性能引起了广泛关注,碳纳米管薄膜的制备是其中一个研究热点。薄膜的制备方法很多,但都具有一定的局限性。本课题采用了一种新颖的方法制备出了纳米量级厚度的单壁碳纳米管薄膜,有望在ITO替代材料、传感器、电磁屏蔽等领域获得应用。由于范德华力的作用,常规制备方法得到的单壁碳纳米管均是成束存在的,我们利用单链DNA为分散助剂,在超声辅助下制备出能够稳定存在的单壁碳纳米管-DNA溶液。TEM、AFM表征结果证实,该溶液中,被DNA缠绕的单壁碳纳米管分散性良好,主要以单根离散和小束形式存在。在制备出均匀稳定的碳纳米管-DNA溶液的基础上,以阳极氧化铝膜为基体,采用浸渍-吸附法,在多孔阳极氧化铝膜与碳纳米管-DNA溶液的固液界面,通过自组装获得了碳纳米管薄膜。并通过光学显微镜、SEM、EDS、IR、拉曼光谱、四探针测试仪等检测手段对所制备的薄膜进行了形貌、结构和导电性能表征,该薄膜厚度均匀仅为纳米级、具有一定的透光性、导电性能良好,方块电阻最低可达780Ω/sq。以制备的单壁碳纳米管-DNA溶液为导电溶液,通过电泳方法,在玻碳电极表面形成了碳纳米管膜,并在铁氰化钾溶液中对该薄膜修饰的玻碳电极的循环伏安性能进行了测试。实验证实,与裸玻碳电极相比,经过碳纳米管膜修饰的玻碳电极测试Fe（CN）₆^4-/Fe（CN）₆^3-氧化还原对的可逆性更好、电流响应更大,表现出良好的灵敏度和稳定性。且随着电泳电压的增大和时间的延长,经碳纳米管膜修饰的玻碳电极在铁氰化钾溶液中的响应信号增大。更多还原

【Abstract】 Carbon nanotube, as one kind of one-dimensional structure materials, has attracted much attention due to its unique optical, electronic, and mechanical properties. And the fabrication of carbon nanotube membrane is one of research highlights. Many approaches have been developed to prepare carbon nanotube membranes, and most of them are of different shortcomings. In this paper, a novel method was proposed to prepare ultra-thin carbon nanotube membrane with just a few nanometers. It has potential applications in the substitute of ITO, sensors, electromagnetic shielding material, and so on.Single-walled carbon nanotubes prepared by normal methods always aggregate into bundles because of van der Waals attraction. We obtained stable carbon nanotube solution using DNA as dispersant with the help of sonication. TEM and AFM images show that the single-walled carbon nanotube is well-dispersed and isolated into individual.Based on the fabrication of well-dispersed and stable carbon nanotube-DNA hydrosol, anodic aluminum oxide was immersed into the hydrosol to prepare carbon nanotube membrane. The membrane could be acquired at the interface of solid and liquid by self-assembling and this method is defined as immersion-adsorption fabrication. The membrane was analysised in details by optical microscope, SEM, EDS, IR, Raman, four-point probes. The results show that the membrane with good homogeneity is very thin, just a few nanometers. The membrane is transparent and possesses excellent electrical conductivity with the lowest square resistance of 780Ω/sq.Carbon nanotube membrane was also obtained on the surface of glassy carbon electrode（GCE） by electrophoretic deposition in carbon nanotube-DNA aqueous solution. Compared with GCE, the modified electrode shows stronger current signals responding and better reversibility towards Fe（CN）₆^4-/Fe（CN）₆^3- in the cyclic voltammetry analysis. Moreover, such electrochemical signals are stable and sensitive. With the increase of voltage and extension of time, the current signals towards Fe（CN）₆^4-/Fe（CN）₆^3- are stronger.更多还原