Interdisciplinary School of Green Energy/Institute of Advanced Materials & Devices, Ulsan National Institute of Science and Technology (UNIST), 100, Banyeon, Ulsan 689-798, South Korea.
ACS Nano. 2011 Mar 22;5(3):2324-31. doi: 10.1021/nn103630y. Epub 2011 Mar 3.
We report an effective route to prepare highly conducting and flexible few-walled carbon nanotube (FWNT) thin films. The free-standing thin films were fabricated by functionalizing FWNTs with 4-ethoxybenzoic acid (EBA) via a direct Friedel-Crafts acylation reaction in a nondestructive polyphosphoric acid/phosphorus pentoxide medium. The resulting ethoxybenzoyl-functionalized FWNT (EBA-f-FWNT) was readily dispersible in water. EBA-f-FWNT thin films were formed by a simple suction filtration of the dispersed solution. Electron microscopic studies were employed to characterize the morphologies of the resulting thin films. The obtained results indicate that the structure of FWNTs was not perturbed by the incorporation of EBA moieties, which were uniformly grafted onto FWNTs forming the FWNT networks. Room temperature electrical conductivity of the thin films was obtained using standard four-probe measurements, which revealed a value as high as 29 400 S m(-1), while the tensile strength and modulus of the film were found to be about 80 MPa and 15 GPa, respectively. Cyclic voltammograms revealed a rectangular shape, with superior capacitive behaviors nearing 133 F/g for the thin films, which is very attractive for capacitor applications.
我们报告了一种有效途径来制备高导电性和柔性的少层碳纳米管（FWNT）薄膜。通过在非破坏性多磷酸/五氧化二磷介质中使用 4-乙氧基苯甲酸（EBA）对 FWNTs 进行直接 Friedel-Crafts 酰化反应，制备了具有自支撑性的薄膜。所得的乙氧基苯甲酰基功能化 FWNT（EBA-f-FWNT）在水中易于分散。通过分散溶液的简单抽吸过滤形成 EBA-f-FWNT 薄膜。电子显微镜研究用于表征所得薄膜的形态。所得结果表明，FWNTs 的结构没有受到 EBA 部分的掺入的影响，EBA 部分均匀地接枝到 FWNTs 上形成 FWNT 网络。使用标准四探针测量法获得了薄膜的室温电导率，其值高达 29400 S m(-1)，而薄膜的拉伸强度和模量分别约为 80 MPa 和 15 GPa。循环伏安法显示出矩形形状，薄膜的电容行为接近 133 F/g，这对于电容器应用非常有吸引力。
