COMPOSITION CONTROL OF FERROELECTRIC NANOPARTICLES USING SUPERCRITICAL FLUIDS

摘要

Pure and well-crystallized Barium Strontium Titanate (BST) nanoparticles with controlled Ba/Sr ratio have been successfully synthesized under supercritical conditions using a continuous-flow reactor in the temperature range of 150-380°C at 26 MPa. To synthesize the Ba_(0.6)Sr_(0.4)TiO_3 composition, alkoxides, ethanol and water were used. The resulting nanopowder consists of fine particles with an average particle size of 23 nm. The results show that the Ba/Sr ratio of this powder can be accurately controlled from the composition of precursor. The characterization of the as-synthesized Ba_(0.6)Sr_(0.4)TiO_3 solid-solution and the dielectric properties of the sintered ceramics are here reported.