Defect chemistry and semiconducting properties of titanium dioxide: II. Defect diagrams☆ Original Research Article

The present work derives defect diagrams for titanium dioxide, TiO2, within a wide range of oxygen partial pressures involving the n-type regime, the p-type regime and the n–p transition regime in the range 973–1373 K. The non-stoichiometry and related defect disorder of TiO2 are considered in terms of defects in both sub-lattices involving: • Oxygen sublattice: oxygen vacancies • Ti sublattice: Ti vacancies and Ti interstitials Defect diagrams are derived in terms of defects concentration (oxygen vacancies, tri- and four-valent Ti interstitials) as a function of oxygen partial pressure) at different levels of acceptor- and donor-type pre-imposed defects (Ti vacancies and foreign cations).