Powder synthesis and properties of LiTaO3 ceramics

• Pure LiTaO3 powder was synthesized at 500 °C by a molten salt technique.
• Pure polycrystalline LiTaO3 ceramics prepared by a pressureless sintering method.
• The ceramics annealed at 1300 °C for 3 h exhibits a Curie temperature of 663 °C.
• The as-prepared LiTaO3 ceramics have good ferroelectric properties.

The LiTaO3 powders with sub micrometer grade grain size have been synthesized successfully using a molten salt method. Lithium tantalate began to form at 400 °C reaction temperature and transformed to pure phase without residual reactants when it was processed at 500 °C for 4 h in static air. The undoped LiTaO3 ceramics with a Curie temperature about 663 °C were obtained by pressureless sintering at 1300 °C for 3 h. The relative dielectric constant (ɛr) increases from 50 to 375 at temperature ranging from 30 to 663 °C and then decreases quickly as the temperature increases above 663 °C. The ceramics shows a relative dielectric constant of 49.4, a dielectric loss factor (tan δ) of 0.007, a coercive field (Ec) of 28.66 kV/cm and a remnant polarization (Pr) of 32.48 μC/cm2 at room temperature.

The pure LiTaO3 ceramics with a Curie temperature about 663 °C were obtained by pressureless sintering at 1300 °C for 3 h. The relative dielectric constant (ɛr) increases from 50 to 375 at temperature ranging from 30 to 663 °C and then decreases quickly as the temperature increases above 663 °C. The ceramics shows a relative dielectric constant of 49.4, a dielectric loss factor (tan δ) of 0.007, a coercive field (Ec) of 28.66 kV/cm and a remnant polarization (Pr) of 32.48 μC/cm2 at room temperature.Figure optionsDownload as PowerPoint slide