Ab initio study of electronic and optical properties of nitrogen-doped rutile TiO2

Abstract

Ab initio study has been carried out to investigate the band structure, density of state and optical dielectric function of pure and Nitrogen (N)-doped rutile phase of TiO2. The band structure obtained with the inclusion of U parameter of 8.5 eV compared favorably with experimental result. Bandgap of N-doped rutile decreases with respect to pure rutile which is traceable to 2p state of the Nitrogen dopant as revealed in partial density of state (PDOS). The optical properties calculated revealed that N-doped rutile has at least one optical peak in the visible light region of the electromagnetic spectrum which suggests it to be a potential material for photovoltaic application than pure rutile. Our results suggest that optical properties of rutile can be adapted by doping with Nitrogen at different concentration which enhances its potential as photocatalyst.