ABSTRACT
Polymer host multiferroic nanocomposites are appropriate for device application because they are highly flexible and can be cast in thin film form. Ceramic polymer composites have become potential candidates for integration into high-frequency electronics. For many applications including integral thin film capacitors, electrostriction systems, for artificial muscles and electric stress control devices, apart from a high dielectric constant, a low dielectric loss is also required. In particular, one-dimensional ferroelectric materials have recently been studied extensively in the quest to miniaturize devices for nonvolatile random access memory applications and discovering interesting physical phenomena at nanoscale. Fabrication of polymer fibers with diameters in the range of micrometers and nanometers has attracted the attention of several researchers in recent times all over the globe. Significant improvement in the magnetoelectric (ME) response is observed in polymer-based nanocomposite films. Polymethyl methacrylate (PMMA) has been chosen as the matrix due 176to low dielectric loss of the polymer. In this chapter, the fabrication and characterization of BiFeO3-–NaNbO3–PMMA films are detailed. The PMMA–BiFeO3–NaNbO3 films were prepared by solvent casting method. Structural analysis was performed using X-ray diffraction, scanning electron microscope, atomic force microscopy, and confocal Raman spectroscopy. The ME coupling studies confirmed the multiferroic nature of the film composites at room temperature. The magnetization measurements have shown a weak ferromagnetic behavior at room temperature for both film and fiber composites. The dielectric study of the composite shows low dielectric loss compared to bulk BiFeO3. The electric property is due to the ferroelectric phase of NaNbO3 and poly (methyl methacrylate). The present findings may lead to an easy and cheap method for preparing flexible energy storing and transforming materials which are required in embedded-capacitors, microelectromechanical systems, ultrasonic resonators, high-power transducers, actuators, and so on.
