Dielectric and pyroelectric properties of barium strontium calcium titanate ceramics

Abstract

Abstract (Ba 0.6 Sr 0.3 Ca 0.1 )TiO 3 powders were prepared by the sol-gel method using a solution of Ba, Sr and Ca acetate and Ti isopropoxide, and the specimens doped with MnCO 3 (0.1 mol%) and Y 2 O 3 (0.5 mol%) were fabricated by the cold isostatic press method. The urethane pot and zirconia ball were used in the mixing and grinding process, and the green pellets were sintered at 1450 °C for 2 h in the alumina crucible. The specimen exhibited a dense and void-free grain structure with grain size of about 3 μm. The dielectric constant and the dielectric loss at Curie temperature were 16,600 and 1.2%, respectively. The specimen under a 4 kV cm −1 DC bias field showed the maximum pyroelectric coefficient of 550×10 −9 C cm −2 K -1 at Curie temperature. The figure of merit F.M.D ∗ for specific detectivity ( D ∗ ) of the specimen, applied with DC 8 kV cm −1 bias field, was the highest value of 17.6×10 −9 C cm J −1 at Curie temperature.