Nonstoichiometry and defect structure of Mn-doped BaTiO3-delta

摘要

Oxygen nonstoichiometry (delta) of 1 m/o Mn-doped polycrystalline BaTiO3-delta has been measured as a function of oxygen partial pressure in the range of 10(-16) less than or equal toP(O2)/atmless than or equal to0.1 at elevated temperatures (900less than or equal toT/degreesCless than or equal to1100) by a solid-state coulometric titration technique. The extent of nonstoichiometry of Mn-doped BaTiO3 is much larger than that of undoped BaTiO3, which is attributed to defect-chemical role of Mn as acceptors. The nonstoichiometry isotherms indicate that Mn-ions change their valence from +4 (or Mn-Ti(X)) to +3 (or Mn-Ti') to +2 (or Mn-Ti'') with decreasing P-O2. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 16]