title: Integrated random-aligned carbon nanotube layers: deformation mechanism under compression.
abstract: Carbon nanotubes have the potential to construct highly compressible and elastic macroscopic structures such as films, aerogels and sponges. The structure-related deformation mechanism determines the mechanical behavior of those structures and niche applications. Here, we show a novel strategy to integrate aligned and random nanotube layers and reveal their deformation mechanism under uniaxial compression with a large range of strain and cyclic testing. Integrated nanotube layers deform sequentially with different mechanisms due to the distinct morphology of each layer. While the aligned layer forms buckles under compression, nanotubes in the random layer tend to be parallel and form bundles, resulting in the integration of quite different properties (strength and stiffness) and correspondingly distinct plateau regions in the stress-strain curves. Our results indicate a great promise of constructing hierarchical carbon nanotube structures with tailored energy absorption properties, for applications such as cushioning and buffering layers in microelectromechanical systems.
authors.affiliation: State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275, P. R. China. guixch@mail.sysu.edu.cn.
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Zeng
authors.forename: Xuchun
authors.initials: X
authors.lastname: Gui
authors.forename: Qiming
authors.initials: Q
authors.lastname: Gan
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Lin
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhu
authors.forename: Wenhui
authors.initials: W
authors.lastname: Zhang
authors.forename: Rong
authors.initials: R
authors.lastname: Xiang
authors.forename: Anyuan
authors.initials: A
authors.lastname: Cao
authors.forename: Zikang
authors.initials: Z
authors.lastname: Tang