Interaction of Acetone Molecules with Carbon-Nanotube-Supported TiO2 Nanoparticles: Possible Applications as Room Temperature Molecular Sensitive Coatings

• DOI: 10.1021/jp064651e
• Publication Date: 2006-11-22T12:01:54Z
• Authors: Ricardo A. Guirad...; Marciano Sánchez; Marina E. Rincón
• Keywords: Surface Modification; Carbon fibers

Room-temperature detection of acetone by TiO2/multiwall carbon nanotube (MWCNT) sol−gel composites is reported. We found a sizable increase in the resistance during adsorption, best performance being obtained on synthesized Ti-isopropoxide route and containing functionalized MWCNTs. Sensors based these were highly reproducible, with fast adsorption/desorption cycles at room temperature, showing linear response to concentration up 4000 ppm. In order better understand our experimental results, some relevant surface reactions have been analyzed detail performing both ab initio Hartree−Fock density functional theory calculations adsorption model bare chemically (by attaching O, Ti, OH groups as well small TixOy clusters) single-wall nanotubes. Interestingly, TiO2/carbon compounds seems be mainly dependent precise details coordination environment around Ti sites, explaining desorption Our theoretical results are consistent measured variations upon exposure confirms thus hole primary carrier hybrid materials