Sol-gel synthesis and spark plasma sintering of Ba0.5Sr0.5TiO3

Ultrafine Ba0.5Sr0.5TiO3 powders were prepared by using barium nitrate, strontium nitrate, tetrabutyl titanate, and ammonia via citrate-nitrate combustion process at low temperature (500 degreesC), along with the X-ray diffraction (XRD), differential scanning calorimetry (DSC)/thermogravimetry analysis (TGA) and scanning electron microscopy (SEM) analytic reports. Spark plasma sintering was carried out to obtain the ultrafine crystalline BST and to improve the dielectric properity. It was found that the sintered BST showed ultrafine crystalline microstructure. At 25 degreesC, the dielectric constant and dissipation factor of the sintered sample were 1533 and 0.0063 at 10 kHz. (C) 2004 Elsevier B.V. All rights reserved.