Lee Jae-Hyeok, Kang Won-Seok, Nam Gwang-Hyeon, Choi Sung-Wook, Kim Jae-Ho
Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Korea.
J Nanosci Nanotechnol. 2009 Dec;9(12):7080-4. doi: 10.1166/jnn.2009.1615.
Hierarchically-aligned single-walled carbon nanotube (SWNT) films over large areas were fabricated by using Langmuir-Blodgett (LB) technique. Thiophenyl-modified SWNTs spreading solution in chloroform was prepared through amidation reaction of oxidized SWNTs. The resulting SWNTs were found to form stable colloidal suspensions in organic solvents, such as chloroform, which is a suitable solvent for the LB application. The compression of the thiophenyl-modified SWNTs spread onto the water surface of an LB trough leading to a uniform SWNT Langmuir monolayer, where SWNTs were aligned parallel to the trough barrier. Optical anisotropy of SWNTs LB films on quartz substrate was confirmed by polarized UV-Vis/NIR spectroscopic measurement. Moreover, the electrical conductivity of the resulting SWNT films, which were parallel to the tube axis, was found to be approximately 15 times higher than those that were perpendicular to the axis, reflecting anisotropic electrical properties due to the uniaxial alignment of individual SWNT bundles.
通过使用朗缪尔-布洛杰特（LB）技术制备了大面积的分层排列的单壁碳纳米管（SWNT）薄膜。通过氧化单壁碳纳米管的酰胺化反应制备了在氯仿中的硫苯基修饰的单壁碳纳米管铺展溶液。发现所得的单壁碳纳米管在有机溶剂（如氯仿）中形成稳定的胶体悬浮液，氯仿是适用于LB应用的溶剂。将硫苯基修饰的单壁碳纳米管铺展在LB槽的水面上进行压缩，形成均匀的单壁碳纳米管朗缪尔单层，其中单壁碳纳米管与槽的屏障平行排列。通过偏振紫外-可见/近红外光谱测量证实了石英衬底上单壁碳纳米管LB薄膜的光学各向异性。此外，发现所得单壁碳纳米管薄膜平行于管轴方向的电导率比垂直于轴方向的电导率高约15倍，这反映了由于单个单壁碳纳米管束的单轴排列而产生的各向异性电学性质。
