Multiferroic Properties of Ti-doped BiFeO3 Ceramics

Abstract

Bi(Fe1-xTix)O-3 (x = 0, 0.005, 0.01, 0.015) ceramics were prepared by using a conventional solid state reaction method. The influences of Ti doping on the crystal structure and the microstructure and on the dielectric, ferroelectric, and magnetic properties of the BiFeO3 ceramics were investigated by using X-ray diffraction, scanning electron microscopy, dielectric measurements, and ferroelectric and magnetic hysteresis measurements. As the amount of Ti substitution was increased, the dielectric loss and the variation in the loss with increasing frequency decreased, and the ferroelectric hysteresis loops changed from rounded to a typical ferroelectric feature. Also, with increasing Ti concentration, the magnetization and the coercive magnetic field increased. Experimental results suggested that partial substitution of high-valance, smaller ionic radius, and nonmagnetic Ti at the Fe site led to a reduction in oxygen vacancies and to a change in the antiferromagnetic structure, resulting in a reduced leakage current and reduced net magnetization, respectively.