Electrical properties of (Na,Ce) doped Bi5Ti3FeO15 ceramics

Bi5Ti3FeO15 (BTF) doped with (Na,Ce) was prepared by solid-state reaction sintering. Effects of (Na, Ce) doping on the structure, microstructure, and electrical properties of BTF were investigated. The Curie point decreased from 759 to 711 degrees C with increasing dopant amount. At low temperatures (50-400 degrees C), peaks of dielectric losses only can be seen for BTF, Bi4.95Na0.025Ce0.025Ti3FeO15, and Bi4.90Na0.05Ce0.05Ti3FeO15 ceramics. The highest piezoelectric constant d(33) of 13.4 pC/N is achieved for Bi4.80Na0.10Ce0.10Ti3FeO15 ceramics. At an applied electric field of 200 kV/cm, the polarization-electrical field and the current-electrical field hysteresis loops of Bi4.90Na0.05Ce0.05Ti3FeO15 ceramics are shown. This composition also has the highest room-temperature resistivity, about 8 x 10(12) Omega.cm. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim