Effects of La content on the properties of Ba1?xLaxTiO3 powders prepared by spray pyrolysis

摘要

Nano-sized Ba1?xLa x TiO3 (0 ≤ x ≤ 0.03) powders were prepared by ultrasonic spray pyrolysis from the spray solution with citric acid. The mean sizes of the primary particles decreased from 110 nm to 59 nm when the x of the Ba1?xLaxTiO3 powders was changed from 0 to 0.03. The BET surface areas of the powders changed from 9.1 m2/g to 16.9 m2/g. The pure BaTiO3 and La-doped BaTiO3 powders had both tetragonal and cubic crystal structures. The average grain size of the sintered BaTiO3 specimen was 2.8 μm, while those of the La-doped BaTiO3 pellets ranged from 1.04 μm to 0.68 μm according to the doping concentrations of La. The dielectric constant of Ba1?xLaxTiO3 (0.01 ≤ x ≤ 0.03) pellets ranged from 2500 to 3855 when sintered at 1280 °C.