Ab initio study of phase stability in doped TiO 2

摘要: Ab initio density functional theory calculations of the relative stability anatase and rutile polymorphs TiO2 were carried out using all-electron atomic orbitals methods with local approximation. The phase exhibited a moderate margin ~ 3 meV to in pristine material. From computational analysis formation energies Si, Al, Fe F dopants various charge states across different Fermi level rutile, it was found that cationic are most stable Ti substitutional lattice positions while energy is minimised for F− doping interstitial positions. All considerably stabilise phase, suggesting transformation inhibited such systems ranked F > Si > Fe > Al order stabilisation strength. Al act as shallow acceptors compensation achieved through mobile carriers rather than anion vacancies.