SYNTHESIS AND CHARACTERIZATION OF AURIVILLIUS-PHASE Bi_4Sr_(n-3)Ti_No_(3n+3) (n = 3 AND 4) NANOFERROELECTRIC CERAMICS

摘要

Bi_4Ti_3O_(12) (BIT) and Bi_4SrTi_4O_(15) (BIST) ceramics with particle sizes of approximately 36 and 27 nm, respectively, have been successfully prepared by a new poly(ethylene glycol methacrylateco-acrylic acid)-based copolymerization method. XRD, FTIR, and Raman investigations on the BIT and BIST samples revealed that the phase pure nanosized ferroelectric samples were obtained relatively at lower temperatures compared to other techniques. The phase transition temperatures and the peak dielectric constant observed at the Curie temperatures for nanosized BIT and BIST samples obtained in this work are higher than that of conventional ceramic samples with micrometer grain size.