Hydrothermal synthesis and dielectric properties of lanthanum titanate ceramics

Abstract

Lanthanum titanate (La_2/3TiO₃) powders were synthesized by hydrothermal method based on the reaction of TiO₂, La(NO₃)₃ and KOH at 160 °C for 24 h followed by the treatment of acidification. The microstructure, morphology and dielectric properties were investigated by using X-ray diffraction, scanning electron microscope, transmission electron microscope and impedance method. The results show that the La_2/3 TiO₃ particles consist of nearly homogenous and lamellar grains. The particles can be sintered into porous ceramics above 1150 °C. The dielectric properties of La_2/3 TiO₃ show that both the dielectric constant and the dielectric loss tangent decrease with the increase of frequency.

Keywords

lanthanum titanate / dielectric properties / hydrothermal synthesis

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