First principle study of electronic, optical and electrical properties of Mo doped TiO2

Abstract

In this work, the Full Potential Linearized Enhanced Plane Wave Method (FP-LAPW), based on the Density Functional Theory (DFT) and Boltzmann's Transport Theory were used to investigate theoretically the electronic structure, optical and electrical properties of Molebynium doped rutile TiO2 for various concentrations (12%, 6.5%, 2.7% and 1.8%). The Tran-Blaha modified Becke-Johnson exchange potential (TB-mBJ) approximation, has been implemented mainly to improve the electronic structure description. The calculated band structure and the density of states (DOS) explain that the Mo atom is an abundant donor in TiO2, it reduces the bandgap of this material (from 2.72 eV of TiO2 to 2.61 eV of Ti0982Mo0.018O2) and efficiently increase the optical absorption in the visible, which originates from the Mo-4d intra-band transition between valence and conduction bands. The fermi level of pure TiO2 which is at the top of the valence band, shifts towards the conduction band and shows similar metal characteristics after the Mo atoms are introduced into the TiO2 supercell. We found also as a result that Mo doped rutile TiO2 material have high conductivity and low resistivity of the order of (1–5) 10−5cm.