Structure–property relationships in (1 − x)BaTiO3–xBiGdO3 ceramics. Issue 9 (September 2015)

• Record Type: Journal Article
• Authors: Schileo, Giorgio; Feteira, Antonio; Reichmann, Klaus; Li, Ming; Sinclair, Derek C.
• Is Part Of: Journal of the European Ceramic Society. Volume 35:Issue 9(2015:Sep.)
• Page Start: 2479
• Page End: 2488
• Publication Date: 2015-09
• Subjects: Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2015.03.004
• Languages: English
• ISSNs: 0955-2219

Abstract

<abstract abstract-type="author" id="abs0005"> <title id="sect0005">Abstract</title> <sec> <p id="spar0005">(1 − <italic>x</italic>)BaTiO₃–<italic>x</italic>BiGdO₃ ceramics were prepared by the solid state reaction method. X-ray diffraction and Raman spectroscopy indicate a maximum co-solubility of Bi/Gd in BaTiO₃ at <italic>x</italic> = 0.10 with a change of symmetry from tetragonal to pseudo-cubic at <italic>x</italic> = 0.08. Backscattered electron images, however, reveal the presence of a secondary phase in <italic>x</italic> ≥ 0.06. The dielectric behaviour evolves continuously with <italic>x</italic> from a classical ferroelectric to a typical relaxor and this transition is accompanied by a shift in the permittivity maxima towards lower temperatures. The presence of two dielectric anomalies for <italic>x</italic> ≥ 0.06 is associated with residual core–shell structures, as revealed by transmission electron microscopy. The dielectric anomaly associated with the core regions remains at ∼120 °C, whereas the other anomaly decreases continuously towards lower temperature with <italic>x</italic>. This study shows that chemical equilibrium is much more difficult to achieve than in other (1 − <italic>x</italic>)BaTiO₃–<italic>x</italic>Bi[Me]O₃ systems, where Me is Yb or Sc.</p> </sec> </abstract>