Optimization of Magneto-Electric Coupling in PVDF/PVDF-TrFE/Fe₃O₄ Thin Film Nanocomposites for MEMS Sensor Devices

Abstract

Magnetoelectric materials which simultaneously exhibit ferroelectricity and magnetism have attracted great attention in recent years due to their potent coupling effect, and potential application in the electronics industry. The work done in this study aims to investigate the effect of ferromagnetic (Fe3O4) nanoparticles on the thermal, mechanical, magnetic, and ferro-electrical properties of PVDF, and its co-polymer poly (vinlydene fluoride-co-trifluoroethylene), P (VDF-TrFE). These compounds are synthesized into flexible nanocomposite thin films, via a novel solvent casting method to influence crystallization and nucleation growth. Fe3O4 nanoparticles (NP) were integrated with polymers at varying weight percentages (1wt%, 3wt%, 5wt%, 7wt%, and 10wt %). Magnetoelectric nanocomposites were annealed at 150oC. Films were fabricated and processed at dimensions: 8-20μm thickness, 35 mm length, and 35 mm width. Neat and loaded samples are characterized using x-ray diffraction (XRD) to observe crystallinity and to obtain β - phase content distribution. Ferroelectric hysteresis loops are given from Radiant Multiferroic Analyzer, which resulted in an increase in peak polarization of 9.601μC/cm2 with the addition of 5wt% magnetite nanoparticles to P(VDF-TrFE) polymer blend. Magnetic tests are done using Vibrating Sample Magnetometer (VSM), which yields the magnetic polarization with respect to changes in field magnitude. The highest magnetic moment occurs with the addition of 10wt% Fe3O4 nanoparticles at 3.66 emu/g. Target applications of nanocomposites are for microelectromechanical system (MEMS) devices such as memory cards, spintronic, sensors, electromagnetic shielding, and compact energy storage.