Structural, Optical, and Dielectric Properties of Gadolinium Substituted Barium Titanate

Abstract

In this paper, the sol–gel method is used to synthesize the BaGd_xTi_1-xO_3-x/2□x/2 samples with x = 0.00, 0.01, 0.02, 0.03, 0.04, and 0.05. X-ray diffraction (XRD), spectroscopy Raman, scanning electron microscopy (SEM), and spectroscopy UV–visible have been employed to characterize the structure and morphology of the as-prepared samples. X-ray diffraction analysis indicated the formation of a tetragonal structure with the detection of pyrochlores phases with small intensity. Raman spectroscopy reveals the coexistence of bands characteristic of the tetragonal phase. SEM and EDS images demonstrate that the distribution of the grain is spherical with lower density and the average grain size of BGxT ceramics changes with the increase in Gd content. The UV–VIS spectra of samples were applied in the 200 to 900 nm spectral range and show that the transmittance values are about 60 and 80 and the absorbance values are lower than 12%. The dielectric properties as a function of temperature and as a function of frequency are also studied and show a decrease progressively in the dielectric constant with an increase in the Gd ratio.