Silica-based nanocomposite thin films with mesoporous structure are very interesting materials for gas sensing applications. The porosity of matrix provides a path for the gas molecules to reach the functional oxide nanoparticles and the films show reversible change in resistance and/or optical transmittance in the VIS-NIR range when exposed to gases. Co oxides-SiO(2) and ZnO-SiO(2) mesoporous nanocomposite thin films have been obtained using a pre-hydrolyzed TEOS-based sol, cobalt acetate, zinc acetate and the cationic surfactant cetyltrimetyl ammonium bromide (CTAB). Dip-coating technique has been used for the films deposition. The films were characterized by X-Ray diffraction (XRD), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and optical transmittance. AFM pictures showed uniform mesoporous structure and the XPS spectra reveal the presence of zinc oxide and cobalt oxides in the nanocomposite thin films. The optical transmittance spectra show very good transmittance (between 85-95%) within the visible and new infrared wavelength region.
|Journal||Revue Roumaine De Chimie|
|Publication status||Published - Jul 2007|