With various connectivity schemes

(e.g., 0–3 particulate type, 2–2 laminate type, and 1–3 fiber/rod type), these heterostructures have offered the opportunity to tune ferroelectric and magnetic properties independently, and the ME coefficient is 3 orders of magnitude higher than their single-phase counterparts [7]. The magnetoelectric effect in most multiferroic composites is known as strain-mediated, in which the ME coupling is a concerted result of the piezoelectric effect from the piezoelectric phase and magnetostrictive effect from the magnetic phase. An electric field induces a distortion of the piezoelectric phase, which in turn distorts the magnetostrictive phase, generating a magnetic field and vice versa. Substantial ME coupling requires the ferroelectric phase to be in possession of a high piezoelectric coefficient, CDK inhibition while the magnetic phase possess both high magnetostriction and resistivity, with an intimate mechanical contact between the two [8]. Ceramic composites have a combination of ferroelectric and magnetic oxides; polymer composites have the magnetic oxides embedded in ferroelectric polymer

matrix. The former is limited by high dielectric loss resulting from the interface; the latter offers mechanical flexibility with facile processing. For instance, with high strength Selleckchem GS-7977 and good stability [9], polyvinylidene difluoride (PVDF) and its copolymers such as poly(vinylidenefluoride-co-trifluoroethylene) Montelukast Sodium (P(VDF-TrFE)) [10] and poly(vinylidene fluoride-hexafluoropropylene) (P(VDF-HFP)) [11–13] are well known for their ferroelectricity and piezoelectricity, which make them ideal candidates for multiferroic film fabrication and ME effect exploration. Transition metal ferrites such as CoFe2O4, possessing a large magnetostriction

coefficient (λ ≈ 10−4) [14] and high Curie temperature (T c > 600 K) [15], serve as excellent candidates for the magnetic phase. Although the mechanism of the magnetoelectric coupling is straightforward, complications arise when quantifying the details of polymer-based nanocomposites. The presence of polymorphism (e.g., α, β, γ, δ phases in PVDF), domain walls, grain boundaries, residual stain/magnetization, surface charge, and voids can significantly hinder the ME effect. Andrew and Clarke [16] found that the inclusion of well-dispersed Ni0.5Zn0.5Fe2O4 nanoparticles in a PVDF matrix can enhance the ferroelectric phase content. Liu et al. [17]. reported epitaxial BaTiO3-CoFe2O4 nanocomposite thin films (thickness, 100 nm) with phase transition mediated by tensile strain. Recently, a magnetoelectric coupling coefficient of 12 V/cm · Oe was obtained for P(VDF-HFP)/Metglas laminates [18]. Martins et al. [19] fabricated ferrites/PVDF nanocomposites films with thickness of 40 to 50 μm by solvent casting and melt processing. Guo and co-workers prepared particulate Ni0.5Zn0.