title: Carbon : nickel nanocomposite templates - predefined stable catalysts for diameter-controlled growth of single-walled carbon nanotubes.
abstract: Carbon : nickel (C : Ni) nanocomposite templates (NCTs) were used as catalyst precursors for diameter-controlled growth of single-walled carbon nanotubes (SWCNTs) by chemical vapor deposition (CVD). Two NCT types of 2 nm thickness were prepared by ion beam co-sputtering without (type I) or with assisting Ar(+) ion irradiation (type II). NCT type I comprised Ni-rich nanoparticles (NPs) with defined diameter in an amorphous carbon matrix, while NCT type II was a homogenous C : Ni film. Based on the Raman spectra of more than 600 individual SWCNTs, the diameter distribution obtained from both types of NCT was determined. SWCNTs with a selective, monomodal diameter distribution are obtained from NCT type I. About 50% of the SWCNTs have a diameter of (1.36 ± 0.10) nm. In contrast to NCT type I, SWCNTs with a non-selective, relatively homogeneous diameter distribution from 0.80 to 1.40 nm covering 88% of all SWCNTs are obtained from NCT type II. From both catalyst templates predominantly separated as-grown SWCNTs are obtained. They are free of solvents or surfactants, exhibit a low degree of bundling and contain negligible amounts of MWCNTs. The study demonstrates the advantage of predefined catalysts for diameter-controlled SWCNT synthesis in comparison to in situ formed catalysts.
authors.affiliation: Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, 01328 Dresden, Germany. matthias.krause@hzdr.de.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Melkhanova
authors.forename: Miro
authors.initials: M
authors.lastname: Haluska
authors.forename: René
authors.initials: R
authors.lastname: Hübner
authors.forename: Tim
authors.initials: T
authors.lastname: Kunze
authors.forename: Adrian
authors.initials: A
authors.lastname: Keller
authors.forename: Gintautas
authors.initials: G
authors.lastname: Abrasonis
authors.forename: Sibylle
authors.initials: S
authors.lastname: Gemming
authors.forename: Matthias
authors.initials: M
authors.lastname: Krause