Effects of the concentration of heavily oxygen vacancy of rutile TiO2 on electric conductivity performance from first principles study

The band structures and the total densities of states of pure and the different concentrations of heavily oxygen vacancy of rutile TiO2-x (x=0, 0.125, 0.25) supercell are studied by using the plane-wave ultrasoft pseudopotential method based on the the density functional theory. Local density approximation +U is used to correct band gaps. The results show that the higher the concentration of heavy oxygen vacancy, the narrower the gap of rutile TiO2 is, the smaller the effective mass of electron is, the lower the electron mobility is, and the lower the electron conductivity is. The calculation results are in agreement with the experimental results.