J-C Charlier et al 2009 Nanotechnology 20 375501 doi:10.1088/0957-4484/20/37/375501
J-C Charlier1, L Arnaud2, I V Avilov2, M Delgado3, F Demoisson4, E H Espinosa5, C P Ewels6, A Felten2, J Guillot7, R Ionescu5, R Leghrib5, E Llobet5, A Mansour7, H-N Migeon7, J-J Pireaux2, F Reniers4, I Suarez-Martinez6, G E Watson8 and Z Zanolli1
Show affiliationsCarbon 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 nano2hybrids is quantified for the detection of toxic species like NO2, CO, C2H5OH and C2H4.
07.07.Df Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing
68.35.Fx Diffusion; interface formation
79.60.Jv Interfaces; heterostructures; nanostructures
68.43.-h Chemisorption/physisorption: adsorbates on surfaces
Condensed matter: electrical, magnetic and optical
Instrumentation and measurement
Issue 37 (16 September 2009)
Received 10 June 2009, in final form 17 July 2009
Published 26 August 2009
J-C Charlier et al 2009 Nanotechnology 20 375501