Effect of Variable Valence Ion Doping on the Dielectric Properties of BaTiO₃–Based Materials

Abstract

Dielectric properties of BaTiO₃, BaTiO₃ + 0.1 wt.% Fe₂O₃ and BaTiO₃ + 1 wt.% Fe₂O₃ ceramics were studied. The dielectric measurements were performed at the temperature ranging from 130 K to 500 K and at the frequency ranging from 0.1 Hz to 10 MHz. Phase transitions were also determined by a thermal analysis in a wide temperature range. Both thermal analysis and electrical characterization techniques show that the temperature of phase transition is shifted towards lower temperatures with increasing Fe₂O₃ content. The changes and diversity of the observed phase transition temperatures occurred as a consequence of the ion substitution. Such behaviour of the investigated polycrystalline materials may be due to the multivalence nature of the incorporated ions.

Keywords:

• BaTiO₃
• Fe-doped BaTiO₃ ceramics
• DSC
• phase transition