Fabrication and mechanical properties of column-particle nanocomposites by multiscale shape-assisted self-assembly

作者：Hirakata Hiroyuki^*; Ajioka Yoshifumi; Yonezu Akio; Minoshima Kohji

来源：Journal of Physics D: Applied Physics , 2012, 45(2): 025302.

DOI：10.1088/0022-3727/45/2/025302

We propose a multiscale shape-assisted self-assembly that combines the growth of ordered nanocolumns by glancing angle deposition (GLAD) and the assembly of colloidal nanoparticles by utilizing capillary force. In this work, in the first self-assembly, a SiO2 nanocolumn array was grown by GLAD wherein the column size and interval were regularly controlled using pre-patterned nuclei on a substrate. In the second self-assembly, SiO2 spherical nanoparticles were assembled into the nanocolumn array using an isopropyl alcohol (IPA) or a water colloidal suspension, creating a column-particle nanocomposite. The location and quantity of the assembled nanoparticles could be controlled by choice of the suspension (IPA or water) and the particle concentration. Loading experiments with a diamond flat punch revealed that the initial stiffness and fracture strength of the nanocomposite are significantly increased compared with the nanocolumn array without nanoparticles. The assembled nanoparticles between the nanocolumns effectively constrained the deformation and fracture of the nanocolumns. The multiscale shape-assisted self-assembly thus enabled the synthesis of column-particle nanocomposites with excellent mechanical properties as well as large surface areas.

• 出版日期2012-1-18