Theoretical Investigation for Neon Doping Effect on the Electronic Structure and Optical Properties of Rutile TiO2 for Photocatalytic Applications by Ab Initio Calculations

The non-metals doping as an anion to alternate the electronic structure and optical absorption property of TiO2, and ultimately, to induce the visible light activity for it have been the purpose of this work. The electronic structure and optical properties of neon-doped rutile TiO2 have been investigated by using the density functional theory with Slater type orbital basis set and correlation. This was done using the PBE96 method as implemented within the HyperChem 7.52 software package with Ne concentration approaching the low level may present in industrial samples of rutile TiO2. Defect states involving substitution of an oxygen atom for a neon atom were studied along with the more stable configuration of one neon substitution. Neon changed the band structure and led to a reduce in the band gap in rutile. This means that neon doping brings the absorption edge into the visible range and therefore increase the photocatalytic activity. A stronger absorption for anionic Ne-doped TiO2 one was predicted, because of the higher position of the impurity state in the band gap. The nonmetal- doped TiO2 could efficiently extend the photo-response of TiO2 to low energy (visible) region.