Diffusion in Nonstoichiometric Oxides

Titanium vacancies in nonstoichiometric TiO2 single crystal

“…Titanium dioxide, TiO 2 , generally is known to be an oxygen deficient compound, TiO 2-x , whose n-type semiconducting properties are associated with oxygen vacancies and titanium interstitials [2][3][4]. The present work shows that the defect disorder of TiO 2 also includes titanium vacancies that form acceptortype centers that are responsible for p-type properties.…”

Oxygen partial pressure and thermal annealing dependent properties of RF magnetron sputtered TiO2−x films

“…This behaviour may support some theoretical concepts like defect disorder and their related properties. In general, TiO 2 is an n-type semiconductor and has donor defects, like oxygen vacancies and titanium interstitials, which cause the deficit of oxygen in TiO 2 À x [32,36,37]. The effect of oxygen vacancies on the carrier density causes the low sheet resistance values, hence minimum resistivity and maximum conductivity can exist at low pO 2 .…”

STRUCTURAL PROPERTIES AND NONSTOICHIOMETRIC BEHAVIOR OF CeO2

“…Mass transport in ceria as well as in other fluorite-related materials is several orders of magnitude faster for anions than for the metal 83,84 . Measurements of bulk oxygen diffusion are relatively scarce in the literature and they are summarised in Table 2 Values of oxygen diffusion calculated using Eq.…”