Amorphous Titanium Oxide Thin Films Prepared by Sol-Gel Method at Ultra-low Temperature

Titanium oxide compound is a kind of important material in environmental protection and chemical industry because of its photocatalytic and nontoxic properties. Most reports focus on the preparation and characterization of TiO2 thin films at temperatures ranging from 350°C to 1000°C. However, there is a dearth of reports in the open literature examining the characterization of titanium oxide thin films annealing at ultra-low temperatures like 200°C. In this study, we used the sol-gel and dip-coated technique to deposit TiO2 thin films on microscope glass substrates and then annealed the films at 200°C for 1h. The thin films prepared were characterized by XRD, FE-SEM, FTIR, XPS, and UV-vis. XRD patterns showed that the titanium dioxide formed was amorphous, while FE-SEM images revealed that the thin films produced have irregular crystal boundaries and a number of surface defects due to low crystallization. XPS analysis confirmed the presence of Ti and O with Ti in the Ti4+ oxidation state, verifying the presence formation of stoichiometric TiO2 films. Finally, the optical analysis showed that the bandgap for titanium oxide films annealed at 200°C is approximately 3.71 eV. The experimental data indicate the probable applications of this material including photocatalysts and UV-resistant glass.