A new (Ba, Ca) (Ti, Zr)O3 based multiferroic composite with large magnetoelectric effect

Abstract

The lead-free ferroelectric 0.5Ba(Zr0.2Ti0.8)O3 − 0.5(Ba0.7Ca0.3)TiO3 (BCZT) is a promising component for multifunctional multiferroics due to its excellent room temperature piezoelectric properties. Having a composition close to the polymorphic phase boundary between the orthorhombic and tetragonal phases, it deserves a case study for analysis of its potential for modern electronics applications. To obtain magnetoelectric coupling, the piezoelectric phase needs to be combined with a suitable magnetostrictive phase. In the current article, we report on the synthesis, dielectric, magnetic, and magnetoelectric characterization of a new magnetoelectric multiferroic composite consisting of BCZT as a piezoelectric phase and CoFe2O4 (CFO) as the magnetostrictive phase. We found that this material is multiferroic at room temperature and manifests a magnetoelectric effect larger than that of BaTiO3 −CoFe2O4 bulk composites with similar content of the ferrite phase.

Enhanced piezomagnetic coefficient of cobalt ferrite ceramics by Ga and Mn doping for magnetoelectric applications

“…Magnetic metallic alloys or spinel oxides are used for the former component, while ferroelectric polymers or perovskite phases are preferred for the latter one. 2,[4][5][6][7][8] Interest in cofired ceramic composites has grown due to their low cost, easy manufacturing, possibility of co-sintering the magnetostrictive and piezoelectric oxide phases, and high electrical resistivity when compared to metallic alloys as Metglas or Terfenol-D. [9][10][11][12][13][14] Among magnetostrictive phases, CoF e 2 O 4 (CFO) stands out because of its very high magnetostriction (λ). 15 However, studies in ME composites formed by CFO-based compositions mostly resulted in ME coefficients lower than those using N iF e 2 O 4 -based magnetostrictive phases.…”

“…15 However, studies in ME composites formed by CFO-based compositions mostly resulted in ME coefficients lower than those using N iF e 2 O 4 -based magnetostrictive phases. 9,13,[16][17][18] This is so because the magnetoelectric coupling in composites results from changes of polarization in the piezoelectric phase caused by the dynamical mechanical deformation of the magnetostrictive one under a varying magnetic field. Thus, the relevant characteristic to obtain high ME coupling is a large strain sensitivity dλ dH (or effective piezomagnetic coefficient), and CFO shows low piezomagnetic coefficient because its high magneto-crystalline anisotropy and coercive field.…”

Dielectric and Energy Storage Properties of Ba(1−x)CaxZryTi(1−y)O3 (BCZT): A Review

“…They also found ε′(f) , frequency dependence of permittivity and found that the ferrite phase partly affected the dielectric response of the composite. They considered BCZT85-CFO15 composite as the best choice for future lead-free materials with higher magnetoelectric properties [126]. Sagar Mane et al prepared multiferroic nanocomposites of x[CoNiFe 2 O 4 ]-(1_x)[0.5(BCT-BZT], x = 0.1, 0.2, 0.3, 0.4, and studied the ε r and tanδ and loss factor as a function of frequency and temperature of the composites.…”

Magnetoelectric and magnetodielectric coupling and microwave resonator characteristics of Ba0.5Sr0.5Nb2O6/CoCr0.4Fe1.6O4 multiferroic composite

“…Several bulk magneto-electric composites with ferrites as the magnetostrictive component and either Pb-based or non-Pb-based oxides as piezo-electric component have been investigated to determine the coupling constant as a function of both the contents of the two components as well as processing parameters 8–14 . Some of the most recent results on bulk composites which are Pb-free are summarized in Table 1 15–25 .…”