High-throughput HSE study on the doping effect in anatase TiO2

Abstract

Titania is a widely used semiconductor due to its excellent optoelectronics and catalytic properties. Doping with other cations or anions by substitution of Ti or O is a common way to adjust the electronic structure of pristine TiO₂. Here, using ab initio calculations at the Heyd–Scuseria–Ernzerhof (HSE06) level, the substitution energy, formation energy and electronic structures of anatase TiO₂ doped with 40 kinds of elements including transition metals, alkali metals, alkaline earth metals, p-block metals, and nonmetals have been studied systematically. It is found that doping with most of these elements can narrow down the band gap of TiO₂, while in some doped systems, a recombination center induced by intermediate bands is also observed. Besides, for transition metal-doped TiO₂ systems, the electron spin state analysis of dopants and the doping level investigation reveal that a relatively high spin structure tends to be formed in Cr, Mn, Fe, Zn, Mo, Tc, Ru and Cd-doped TiO₂, and the doping levels of 4d-orbital transition metals are generally higher than those of 3d-orbital transition metals.