Wang Yanjie, Li Min, Gu Yizhuo, Zhang Xiaohua, Wang Shaokai, Li Qingwen, Zhang Zuoguang
Key Laboratory of Aerospace Advanced Materials and Performance (Ministry of Education), School of Materials Science and Engineering, Beihang University, No. 37 Xueyuan Road, Haidian District, Beijing 100191, China.
Nanoscale. 2015 Feb 21;7(7):3060-6. doi: 10.1039/c4nr06401a.
Carbon nanotubes are ideal scaffolds for designing and architecting flexible graphite films with tunable mechanical, electrical and thermal properties. Herein, we demonstrate that the assembly of aligned carbon nanotubes with different aggregation density and morphology leads to different mechanical properties and anisotropic electrical conduction along the films. Using drying evaporation under tension treatment, the carbon nanotubes can be assembled into strong films with tensile strength and Young's modulus as high as 3.2 GPa and 124 GPa, respectively, leading to a remarkable toughness of 54.38 J g(-1), greatly outperforming conventional graphite films, spider webs and even Kevlar fiber films. Different types of solvents may result in the assembly of CNTs with different aggregation morphology and therefore different modulus. In addition, we reveal that the high density assembly of aligned CNTs correlates with better electric conduction along the axial direction, enabling these flexible graphite films to be both strong and conductive.
碳纳米管是设计和构建具有可调机械、电学和热学性能的柔性石墨薄膜的理想支架。在此，我们证明，具有不同聚集密度和形态的排列碳纳米管的组装会导致不同的机械性能以及沿薄膜的各向异性导电。通过张力处理下的干燥蒸发，碳纳米管可以组装成具有高达3.2 GPa的拉伸强度和124 GPa的杨氏模量的坚固薄膜，从而产生54.38 J g(-1)的显著韧性，大大优于传统石墨薄膜、蜘蛛网甚至凯夫拉纤维薄膜。不同类型的溶剂可能导致具有不同聚集形态的碳纳米管组装，从而具有不同的模量。此外，我们发现排列碳纳米管的高密度组装与沿轴向更好的导电性相关，使这些柔性石墨薄膜兼具强度和导电性。
