Fabrication and characterization of flexible films of poly(vinylidene fluoride)/Pb(Fe0.5Ti0.5)O3-delta multiferroic nano-composite

摘要

Pb(Fe0.5Ti0.5)O3-delta (PTFO) is one of the few multiferroic materials that exhibits coupled co-existence of ferroelectricity and ferromagnetism at room temperature. In this study, phase-pure PTFO multiferroic nanoparticles were dispersed in poly(vinylidene fluoride) (PVDF) matrix via melt-mixing followed by compression molding in order to make flexible film of PVDF/PTFO nanocomposite. Phase pure PTFO nanoparticles with an average particle size of similar to 32 nm were synthesized by co-precipitation method. PVDF/PTFO flexible films were prepared, wherein PTFO nanoparticles were varied from 5-25 wt%. The magnetic, ferroelectric, dielectric, magneto-dielectric coupling and morphology, as well as structural properties of these films were systematically investigated. The well saturated magnetic hysteresis loops could confirm the ferromagnetic properties associated with PVDF/PTFO nanocomposite films. The variation of dielectric permittivity and dielectric loss was investigated at frequencies ranging from 10 Hz to 10 MHz for these nanocomposites. The maximum polarization, saturation magnetization and dielectric permittivity were increased with increasing concentration of the PTFO nanoparticles. The ferroelectric, magnetic and magneto-capacitive behaviour at room temperature could suggest the multiferroic nature of the nanocomposite films with significant magnetodielectric coupling.