THE INFLUENCE OF ETHANOL ON THE MORPHOLOGY, PHASE AND CRYSTAL SIZE OF THE SOL-GEL DIP COATING TiO2 THIN FILMS

Abstract

The effect of ethanol and its concentration on the characteristic of a sol-gel TiO₂ thin film was investigated. Three concentrations (M) of 0 M (without solvent), 3 M and 5 M were prepared by varying ethanol to water ratio in a sol of titanium (IV) isopropoxide as a precursor. A glass slide substrate was dipped into the sol for ten times to produce layers of TiO2 films before finally heated at 500°C for 1-hour. Analysis on the TiO₂ surface morphology was obtained using Scanning Electron Microscope (SEM). Phases and crystal size of the TiO₂ films were analyzed using X-ray diffraction (XRD) and reinforce with Raman Spectroscopy (RS). SEM result showed that surface cracks observed for all deposited TiO₂ film. At 5M of ethanol, the cracks produced were more severe causing films delamination. Mixture of anatase, brookite and rutile phases were identified only with TiO₂ thin film of 0M of ethanol. The effect of ethanol on crystal size, however, was insignificant due to similar crystallite size (~17.29 nm) obtained at 3 M and 5 M. Hence, the development of TiO₂ phases without the use of solvent is emboldening to explore as an attempt toward producing ecological photocatalytic materials via green process.