TiO2 anatase phase structure growth, morphological optical and electrical characterization by different alcoholic solvents

Nanocrystalline TiO₂ anatase thin films have been prepared from alkoxide solution via sol-gel method. The effects of two protic solvents of methanol and ethanol of TiO₂ thin films were systematically investigated under room temperature. The films were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), ultraviolet spectroscopy (UV-vis), current-voltage (I-V) and capacitance-frequency (C-F) test. The structure growth, morphological, optical and electrical characteristic of the TiO₂ thin films were influenced by different factors such as dielectric constant, film thickness, and particle size. XRD confirmed the presence of tetragonal anatase phase in all samples after annealed at 400°C. Furthermore, it was inferred from UV-visible transmittance spectra that although band-gap energy of the films are independent of solvent type, the particle size, film thickness, crystallinity and electrical measurement (I-V and C-F test) of the films are highly affected by the type of solvents.