title: Carbon nanotubes randomly decorated with gold clusters: from nano2hybrid atomic structures to gas sensing prototypes.
abstract: Carbon nanotube surfaces, activated and randomly decorated with metal nanoclusters, have been studied in uniquely combined theoretical and experimental approaches as prototypes for molecular recognition. The key concept is to shape metallic clusters that donate or accept a fractional charge upon adsorption of a target molecule, and modify the electron transport in the nanotube. The present work focuses on a simple system, carbon nanotubes with gold clusters. The nature of the gold-nanotube interaction is studied using first-principles techniques. The numerical simulations predict the binding and diffusion energies of gold atoms at the tube surface, including realistic atomic models for defects potentially present at the nanotube surface. The atomic structure of the gold nanoclusters and their effect on the intrinsic electronic quantum transport properties of the nanotube are also predicted. Experimentally, multi-wall CNTs are decorated with gold clusters using (1) vacuum evaporation, after activation with an RF oxygen plasma and (2) colloid solution injected into an RF atmospheric plasma; the hybrid systems are accurately characterized using XPS and TEM techniques. The response of gas sensors based on these nano(2)hybrids is quantified for the detection of toxic species like NO(2), CO, C(2)H(5)OH and C(2)H(4).
authors.affiliation: Unité de Physico-Chimie et de Physique des Matériaux, European Theoretical Spectroscopy Facility, Université Catholique de Louvain, Place Croix du Sud 1, B-1348 Louvain-la-Neuve, Belgium.
authors.forename: J-C
authors.initials: JC
authors.lastname: Charlier
authors.forename: L
authors.initials: L
authors.lastname: Arnaud
authors.forename: I V
authors.initials: IV
authors.lastname: Avilov
authors.forename: M
authors.initials: M
authors.lastname: Delgado
authors.forename: F
authors.initials: F
authors.lastname: Demoisson
authors.forename: E H
authors.initials: EH
authors.lastname: Espinosa
authors.forename: C P
authors.initials: CP
authors.lastname: Ewels
authors.forename: A
authors.initials: A
authors.lastname: Felten
authors.forename: J
authors.initials: J
authors.lastname: Guillot
authors.forename: R
authors.initials: R
authors.lastname: Ionescu
authors.forename: R
authors.initials: R
authors.lastname: Leghrib
authors.forename: E
authors.initials: E
authors.lastname: Llobet
authors.forename: A
authors.initials: A
authors.lastname: Mansour
authors.forename: H-N
authors.initials: HN
authors.lastname: Migeon
authors.forename: J-J
authors.initials: JJ
authors.lastname: Pireaux
authors.forename: F
authors.initials: F
authors.lastname: Reniers
authors.forename: I
authors.initials: I
authors.lastname: Suarez-Martinez
authors.forename: G E
authors.initials: GE
authors.lastname: Watson
authors.forename: Z
authors.initials: Z
authors.lastname: Zanolli
mesh_terms: D005740:Gases / Q000032:analysis* / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D036103:Nanotechnology / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D005740:Gases; D037742:Nanotubes, Carbon; D006046:Gold