Synthesis and characterization of lead-free K0.5Bi0.5TiO3 ferroelectrics by sol-gel technique

A kind of novel lead-free ferroelectrics, potassium bismuth titanate, K0.5Bi0.5TiO3 (KBT), has been prepared by the sol-gel process. The amorphous dried gels were first transformed into Bi2Ti2O7 phase at low heat-treated temperature and as the temperature increased to 700 degreesC, only pure KBT phase can be observed and there was no evidence of second phase. KBT ferroelectric ceramics were fabricated from the natural sintering of 700 degreesC-treated powders, which have a particle size of 100-200 nm. The KBT ceramics sintered at 1050 degreesC showed typical characteristics of relaxor ferroelectric, and the dielectric properties were better than that prepared by a solid-state reaction method. (C) 2004 Elsevier B.V. All rights reserved.