title: Selective chemical vapor deposition synthesis of double-wall carbon nanotubes on mesoporous silica.
abstract: Double-wall carbon nanotubes (DWNTs) have been selectively synthesized over Fe/Co loaded mesoporous silica by catalytic chemical vapor deposition of alcohol. Several silica materials with desired pore diameter and morphology have been investigated for the DWNT growth. The diameter distribution and selectivity of the DWNT are found to depend on the reaction temperature, pore size, and thermal stability of the support material. A high-yield synthesis of DWNTs has been achieved at 900 degrees C over high-temperature stable mesoporous silica. The outer diameter of DWNTs is found to be in the range of 1.5-5.4 nm with a "d" spacing of 0.38 +/- 0.02 nm between inner and outer layers, which is much larger than those of multiwall carbon nanotubes.
authors.affiliation: CREST, Japan Science and Technology Agency, Nagoya University, Nagoya 464-8602, Japan.
authors.forename: Palanisamy
authors.initials: P
authors.lastname: Ramesh
authors.forename: Toshiya
authors.initials: T
authors.lastname: Okazaki
authors.forename: Risa
authors.initials: R
authors.lastname: Taniguchi
authors.forename: Junichi
authors.initials: J
authors.lastname: Kimura
authors.forename: Toshiki
authors.initials: T
authors.lastname: Sugai
authors.forename: Kenichi
authors.initials: K
authors.lastname: Sato
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ozeki
authors.forename: Hisanori
authors.initials: H
authors.lastname: Shinohara
mesh_terms: D000438:Alcohols / Q000737:chemistry; D002384:Catalysis; D003035:Cobalt / Q000737:chemistry; D006358:Hot Temperature; D007501:Iron / Q000737:chemistry; D008855:Microscopy, Electron, Scanning / Q000379:methods; D046529:Microscopy, Electron, Transmission / Q000379:methods; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010316:Particle Size; D016062:Porosity; D012015:Reference Standards; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods / Q000592:standards; D013499:Surface Properties; D014835:Volatilization; D014961:X-Ray Diffraction
chemical_list: D000438:Alcohols; D037742:Nanotubes, Carbon; D003035:Cobalt; D012822:Silicon Dioxide; D007501:Iron