Effects of Eu and Ca Co-Substitution for the Improvement of Multiferroic Properties of BiFeO_3

摘要

By using a sol-gel method, we prepared pure BiFeO_3 (BFO), Ca-doped and Eu/Ca-codoped BiFeO_3 nanoparticles successfully. We studied the effects of Eu/Ca-codoped on the structural, magnetic and ferroelectric properties of the samples. The X-ray diffraction (XRD) analysis tells us there is a structure transition in the codoped samples. Every performance test has shown that co-doped samples were obtained with the best ferromagnetic properties, with the largest remaining magnetization Mr = 0.20 emμ/g. The main reason for the origin of improved magnetic properties may be the structure transition, which destroys the space modulated spin structure of BFO and significantly releases the locked magnetic. In addition, the doping of Eu into BFO can reduce the leakage current and enhance the ferroelectric properties.