Investigation of structural and electrical properties of Gd3+ ions modified BaZr0.05Ti0.95O3 ceramic

Gadolinium (Gd) doped BaZr0.05Ti0.95O3 ceramic samples with general formula Ba(1-x)Gd2x/3Zr0.05Ti0.95O3 were prepared by the solid state reaction method. The effect of Gd on the structural and dielectric behaviours of BaZr0.05Ti0.95O3 have been studied in detail. X-ray diffraction studies revealed that site substitution by Gd3+ ions had a great impact on the site occupancy of the BaZr0.05Ti0.95O3 pervoskite. The lattice parameters increased up to x = 0.03 followed by a decrease at higher concentration showing both donor and acceptor behaviours of Gd in BaZr0.05Ti0.95O3 matrix. Structural changes were studied by Raman spectroscopy also, which showed the non-linear shifting of the modes with increasing doping concentration. The scanning electron microscopy images showed a drastic modification in grain size with increasing Gd concentration. The effect of substitution of Gd3+ ions in BaZr0.05Ti0.95O3 was investigated by means of dielectric studies and the dielectric behaviour was explained using self-compensation model. The diffusivity in the samples was studied by modified Curie-Weiss law.