Influence of Eu doping on the structural, electrical and optical behavior of Barium Zirconium Titanate ceramic

The influence of Eu3+ doping on the structural, dielectric and optical behavior of Barium Zirconium Titanate (BZT) with general formula Ba1−xEu2x/3Zr0.05Ti0.95O3 (x = 0.00, 0.01, 0.02, 0.03, 0.04, 0.05) has been investigated in the present study. The X-ray diffraction (XRD) data show a phase transition from orthorhombic to tetragonal symmetry due to the incorporation of Eu3+ ions in BaZr0.05Ti0.95O3 matrix. A secondary phase of Eu2Ti2O7 is observed for the composition with x ≥ 0.03. The Raman spectroscopic study confirms the structural change as observed in XRD, while the Fourier transformation infra red (FT-IR) spectra reveal that Eu3+ doping in BZT creates vacancies in the system. The temperature dependent dielectric study shows that the transition temperature and maximum dielectric constant decrease with increase in Eu3+content. It is observed that the dielectric diffuseness increases up to x≤0.02 followed by a decrease at higher concentrations of Eu3+. The optical behavior of prepared samples is studied through UV-visible spectroscopy, and it is found that the optical band-gap value increases with Eu3+ concentration up to 2% and then decreases for higher concentrations (x > 2%).