Synthesis, structural and crystal size effect on the optical properties of sprayed TiO2 thin films: Experiment and DFT TB-mbj

Abstract

In this work, was investigated the structural, optical and electrical properties of the titanium dioxide nanoparticles deposited as thin film using spray pyrolysis technique for a dye synthetized solar cell (DSSC) which provides a technically and economically credible alternative concept to present day p–n junction photovoltaic devices. It was involved in this study, the crystal size that was estimated by Scherrer method with the X-ray diffraction (XRD) patterns and the scanning electron microscopy images (SEM), and the thickness of TiO2 multilayer effects on its physical properties. TiO2 was synthetized using sol-gel dip coating method and grown on a commercial indium tin oxide (ITO) with a thin layer of carbon nanotubes for better electrical conductivity. The Lithium electrolyte was converted into gel for better efficiency and less degradation of the thin layer of the dye synthetized solar cell. Ultraviolet–visible spectroscopy (UV–Vis) was used to get the degradation degree, the light intensity and the optical transmittance and absorbance. For different number of layers of TiO2 thin films, it was investigated the thickness dependence of structural, morphological and optical properties of semiconductor. Ab-initio calculations were used with Linear Augmented Plan Waves method (LAPW) and Tran-Blaha Modified Becke-Johnson Density Functional (TB-mbj) to predict corroborate the electrical, structural and optical properties of the samples.