DEFECT CHEMISTRY AND LOW-LOSS CHARACTERISTICS OF ND-DOPED BATIO3 DIELECTRIC CERAMICS

Dayong Lu, Ji Lv, Xiuyun Sun

ABSTRACT:(Ba1–xNdx)Ti1–x/4O3 (x = 0.03‒0.06) (BNT) ceramics with a single-phase perovskite structure were prepared using the mixed-oxides method. The structure, microstructure, point defects, defect chemistry, and dielectric properties of these ceramics were investigated using X-ray diffraction, scanning electron microscopy, electron paramagnetic resonance, and dielectric measurements. Except for BNT with x = 0.04, all BNT ceramics are semiconductors because of the strong doping effect from A-site Nd3+. The defect chemistry is given. The highest concentrations of Ti vacancies and the intense reduction from Mn3+ or Mn4+ to Mn2+ as well as a small amount of Ba vacancies in BNT with x = 0.04 are responsible for low dielectric loss (< 0.05) over the temperature range −50 to 150 °C.

Keywords:Nd-doped BaTiO3 ceramics, X-ray diffraction, dielectric properties, defect chemistry, electron paramagnetic resonance