title: Self-assembled double ladder structure formed inside carbon nanotubes by encapsulation of H8Si8O12.
abstract: Unique low-dimensional SiO(2)-based nanomaterials can be encapsulated and synthesized inside the nanometer-scale one-dimensional internal spaces of carbon nanotubes (CNTs). In this study, various single-walled CNTs (SWNTs) and double-walled CNTs (DWNTs) having different diameters are used as containers for cubic octameric H(8)Si(8)O(12) molecules. High-resolution transmission electron microscopy (HRTEM), Fourier transform infrared (FT-IR) spectroscopy, and Raman spectroscopy observations revealed that, depending on the diameter of the CNTs, two types of structures are formed inside the SWNTs and DWNTs: In the case of those CNTs having inner diameters ranging from 1.2 to 1.4 nm, a new ordered self-assembled structure composed of H(8)Si(4n)O(8n-4) molecules was formed through the transformation of H(8)Si(8)O(12); however, in the case of CNTs having inner diameters larger than 1.7 nm, a disordered structure was formed. This behavior may indicate that strong interactions occur between the CNTs and the encapsulated H(8)Si(4n)O(8n-4) molecules.
authors.affiliation: Nanotube Research Center, National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8565, Japan. liu-z@aist.go.jp
authors.forename: Zheng
authors.initials: Z
authors.lastname: Liu
authors.forename: Soon-Kil
authors.initials: SK
authors.lastname: Joung
authors.forename: Toshiya
authors.initials: T
authors.lastname: Okazaki
authors.forename: Kazu
authors.initials: K
authors.lastname: Suenaga
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Hagiwara
authors.forename: Tetsu
authors.initials: T
authors.lastname: Ohsuna
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Kuroda
authors.forename: Sumio
authors.initials: S
authors.lastname: Iijima
mesh_terms: D003460:Crystallization / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008968:Molecular Conformation; D036103:Nanotechnology / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010316:Particle Size; D012821:Silanes / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D046911:Macromolecular Substances; D037742:Nanotubes, Carbon; D012821:Silanes