Preparation and properties of multiferroic oxide-based magnetoelectric materials

Multiferroic materials have not only single ferroelectric, ferromagnetic and ferroelastic properties, but also multiferroic coupling effects, which lead to new effects. These coupling effects give these materials the potential for a wide range of applications; they can have many uses, such as energy transducers, sensors, and actuators. Now single oxides or composites and related thin films (e.g., BiFeO₃ and ferrite/PZT) have attracted broad attention due to their coexisting ferromagnetic and ferroelectric properties. In this paper, we discuss the relationship between the microstructure and magnetoelectric properties, and describe some problems and further development issues in this research field. Due to the low Neel or Curie temperature for single phase magnetoelectric materials, they exhibit a magnetoelectric effect only at low temperatures and disappear at room temperature, and thus cannot be used in practical. BiFeO₃ thin films have a high Curie temperature, and will have further applications if the electrical properties and coupling effects can be enhanced. Although magnetoelectric composite materials have better performance than single magnetoelectric materials, there are still some issues to be resolved. Multiferroic materials have recently become a common research topic due to their potentially wide application.