Surface Morphology and Dielectric Behaviour of Gd-Doped Ba(Zr_0.52Ti_0.48)O₃ Nanocrystalline Ceramics

Abstract

Surface analysis, frequency dependent permittivity, impedance and ac conductivity studies of gadolinium (Gd) doped BZT perovskite ceramics having stoichiometry (Ba_1–xGd_x)(Zr_0.52Ti_0.48)O₃ (x = 0.1 and 0.2) were reported. Surface morphology including grain distribution, histogram of area, volume, length and perimeter was examined through atomic force microscope. Surface morphological images showed non-uniform distribution of grains. These compounds exhibited abnormal dielectric losses in the frequency range of 10 kHz to 1 MHz. Anomalous variation in frequency dependent relative permittivity (ϵʹ) behaved as non linear dielectric materials with interesting properties. Substitution of Gd ion in BZT resulted in significant lattice distortion due to strain imported via doping. This distortion caused low impedance which in turn increased the magnitude of ac conductivity.

Keywords:

• Gd-doping
• BZT
• Surface analysis
• Dielectric constant
• ac-conductivity