Electrical properties of niobium doped Bi4Ti3O12-SrBi4Ti4O15 intergrowth ferroelectrics

Nb-doped Bi4Ti3O12-SrBi4Ti4O15 intergrowth ceramics have been prepared by modified oxalate route. XRD phase analysis confirmed the formation of single phase compound. Nb-doping does not affect the basic crystal structure of the intergrowth. SEM micrographs showed that the grain size of the ceramics decreases with Nb-doping. The temperature dependence of dielectric constant and losses was investigated in the temperature range 30–800 °C and frequency range 1 kHz–1 MHz. With Nb-doping, the Tc of the ferroelectrics reduces and peak permittivity increases. Doping also introduces small relaxor behavior in the ferroelectrics. The dc conductivity of the ceramics decreases with doping. The remnant polarization (Pr) of the intergrowth ferroelectrics is increased with Nb doping.