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Polar Order Evolutions near the Rhombohedral to Pseudocubic and Tetragonal to Pseudocubic Phase Boundaries of the BiFeO₃-BaTiO₃ System.

ABSTRACT: Solid solutions of (1-x)BiFeO₃-xBaTiO₃ (BF-BT, 0.05 ≤ x ≤ 0.98) were prepared and characterized. It was found that the dielectric constant ε_m, remnant polarization P_r and piezoelectric coefficient d₃₃ reach their maximum values near the rhombohedral-pseudocubic phase boundary. In particular, the 0.7BF-0.3BT composition shows large polarization (P_r > 20 μC/cm²) and a temperature-stable piezoelectric property (d₃₃ > 100 pC/N when the annealing temperature is lower than ~400 °C). Near the tetragonal-pseudocubic phase boundary, ε_m and P_r decrease, and the piezoelectric property vanishes when the BF content reaches 4 mol %.

SUBMITTER: Wei Y

PROVIDER: S-EPMC5458829 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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Polar Order Evolutions near the Rhombohedral to Pseudocubic and Tetragonal to Pseudocubic Phase Boundaries of the BiFeO₃-BaTiO₃ System.

Wei Yongxing Y Jin Changqing C Zeng Yiming Y Wang Xiaotao X Xu Gang G Wang Xiaoli X

Materials (Basel, Switzerland) 20151202 12

Solid solutions of (1-x)BiFeO₃-xBaTiO₃ (BF-BT, 0.05 ≤ x ≤ 0.98) were prepared and characterized. It was found that the dielectric constant εm, remnant polarization Pr and piezoelectric coefficient d33 reach their maximum values near the rhombohedral-pseudocubic phase boundary. In particular, the 0.7BF-0.3BT composition shows large polarization (Pr > 20 μC/cm²) and a temperature-stable piezoelectric prope ...[more]

PMID: 28793715

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