Optical properties of the anatase phase of titanium dioxide thin films prepared by electrostatic spray deposition

Abstract

Titanium Dioxide (TiO2) thin films were prepared by electrostatic spray deposition using 12.5ml of propanol, 10 ml of glacial acetic acid and 1.4ml of titanium (iii) chloride (TiCl3) as precursor. These mixtures were deposited on microscope glass slide on a heated substrate at a temperature of 370 and 420°C with constant time of 10 min. The films were characterized using UV- visible spectrometer (UV–vis), with an integration time of 21 and 150 min for transmittance and reflectance respectively. From
the results obtained from the transmittance spectra it was observed that TiO2 thin film gives a visible transmittance of 86 and 79% at deposition temperature of 370 and 420°C, the films also displayed a high absorbance at 420°C and decreases at 370°C. This shows that high absorbance gives rise to a low transmittance. The optical band gap values gotten from the extrapolation of the linear part were 3.88 eV and 3.81 eV, which is in line with other Anatase that is 3.8 eV and the refractive index was also evaluated.