Phase transition characteristics and dielectric properties of rare-earth (La, Pr, Nd, Gd) doped Ba(Zr0.09Ti0.91)O3 ceramics (original) (raw)
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La 2 O 3 doped barium zirconium titanate Ba 1-x La x Zr 0.15 Ti 0.85 O 3 (BLZT) ceramics have been fabricated by conventional dry route method. Barium carbonate, zirconium oxide, titanium dioxide and lanthanum oxide were the starting material. The dielectric properties of Ba 1-x La x 0Zr 0.15 Ti 0.85 O 3 ceramics have been Investigated. La 3+ ions substitute for A-site Ba 2+ ions to enter the unit cell maintaining the perovskite structure of solid solution and induce the occurrence of ferroelectric relaxor behaviour. BLZT ceramics were prepared by mixing, drying and calcining the raw material which were heated in an alumina crucible at 1300˚c for 4hrs and then re-milled and sintered at 1350˚c for 2hrs. The samples were characterized using X-ray diffraction (XRD).It was observed that the Curie temperature (Tc) of (Ba 1-x La x) Zr 0.15 Ti 0.85 O 3 ceramics is remarkably shifted to lower temperature with increase of x.
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