Electronic and Optical Properties of TiO2 Thin Films: Combined Experimental and Theoretical Study

摘要

In this work, we report the electronic, optical and electrical properties of rutile and anatase crystalline phases of titanium dioxide (TiO2) using first-principles calculations based on density functional theory and experimentally prepared sol precursor using spin coating into glass substrates. X-ray diffraction, atomic force microscopy and ultraviolet-visible-near-infrared spectrophotometry were used to obtain, respectively, structural, morphological and optical properties of deposited films. The theoretical results showed a wide band gap of 2.52 and 3.00 eV for the rutile and anatase phases, respectively, which is consistent with the experimental results found. The measured transmittance of TiO2 reveals that they have high optical transmission (> 80%) and high refractive index in the visible region. Ab initio calculations were also performed with a comparison between Perdew, Burke and Ernzerhof Generalized Gradient and Tran-Blaha Modified Becke-Johnson approximations to calculate complex dielectric function, reflectivity, absorption, electrical, as well as thermal conductivity in the wavelength range of 100-1000 nm.