Magnesium doped titania (TiO2) thin films: deposition, structural, morphological and optical properties

Pure and magnesium (Mg) doped titania (TiO2) thin films were prepared on glass substrates by sol-gel method with dopant concentration varying up to 9.39 atomic % (metal base). The morphological, structural and optical properties were investigated by field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), X-ray diffraction (XRD) and ultraviolet-visible spectroscopy (UV-VIS). Results revealed that the films were highly crystalline and consist of brookite phase of titania, without any other phase such as magnesium oxide. Microstructures showed shrinkage cracking and decrease in root mean square resistance with increase in doping concentration. The optical transmittance has shown a decrease due to scattering of light through cracks and increases with increase in doping concentration. Moreover, the increase in band gap of titania has been observed from 1.81 eV to 2.52 eV.