Temperature stable dielectric properties of lead-free BiFeO 3 –BaTiO 3 modified with LiTaO 3 ceramics
- Citation data:
Materials Letters, ISSN: 0167-577X, Vol: 217, Page: 16-19
- Publication Year:
- Materials Science; Physics and Astronomy; Engineering
LiTaO 3 (LT)-modified (1 − x )(0.675BiFeO 3 –0.325BaTiO 3 ) + 0.6 mol% MnO 2 + 0.4 mol% CuO (BFBTMC– x LT, where x = 0–0.030) ceramics were synthesized by solid state reaction method. The crystal symmetry, ferroelectric response, and temperature stable dielectric properties were investigated as a function of different LT-content. The X-ray diffraction study of BFBTMC–LT piezoceramics revealed no remarkable variation in the crystal symmetry. The value of maximum polarization ( P m ≈ 24 μC/cm 2 ) and remnant polarization ( P r ≈ 18 μC/cm 2 ) were obtained at BFBTMC–0.010LT composition. The maximum temperature of permittivity ( T max ) decreased by the addition of LT-content in BFBTMC materials. The un-doped sample was ferroelectric; a change to relaxor behavior occurred by the addition of LT-content, with broad frequency dependent curves of dielectric mid-value permittivity (ε rmid ) and tangent loss as a function of temperature. A significant enhancement occurred at 3 mol% LT-modified BFBTMC ceramics, with ε rmid = 5000 ± 9.5% (250–450 °C at 1 kHz). These results are favorable for practical applications in high temperature dielectrics.