Magnetic field assisted self-assembly of ferrite-ferroelectric core-shell nanofibers and studies on magneto-electric interactions

Abstract

Core-shell nanofibers of nickel ferrite and lead zirconate titanate have been synthesized by electrospinning, assembled into superstructure in uniform or non-uniform magnetic fields, and have been characterized in terms of ferroic order parameters and strain mediated magneto-electric (ME) coupling. The core-shell structure was confirmed by electron microscopy and scanning probe microscopy. Studies on magnetic field induced polarization P in assembled samples showed a decrease or increase in P, depending on the nature of fibers and strengthening of ME coupling with change in remnant-P as high as 32%. Strong ME interactions were evident from H-induced variation in permittivity at 20–22 GHz.

Multiferroic Core-Shell Nanofibers, Assembly in a Magnetic Field, and Studies on Magneto-Electric Interactions

“…Thus, it is evident from the results in Figure 4 that a strong strain-mediated ME coupling is present in the core-shell fibers and that the nature of coupling depends on the ferroic phases in the core and the shell. The data in Figure 4 compare favorably with H -induced change in polarization reported for core–shell fibers of NFO and PZT [ 34 ].…”

“…Then, 1.767 g of nickel (II) acetate tetrahydrate [Ni(CH 3 COO) 2 4H 2 O] and iron (III) nitrate monohydrate [(Fe(NO 3 ) 3 9H 2 O)] with 1:2 molar ratios of Ni:Fe were added to the PVP/ethanol/water solution and further magnetically stirred for about 20 h at room temperature to form a homogeneous viscous solution with PVP concentration of 6 wt. % for electrospinning [ 34 , 37 ]. The procedure for the preparation of the sol-gel of BaTiO 3 is as follows [ 36 , 37 ].…”

“…Fibers with nanocrystals of ferrite and PZT were made by gel-thermal decomposition and electrospinning was used for fibers with alternate layers of ferrite and PZT or coaxial fibers [ 31 , 32 , 33 ]. We recently reported on the synthesis of nickel ferrite–PZT core–shell nanofibers by electrospinning and measurements of ME coupling by H -induced polarization and magneto–dielectric effects [ 34 ].…”

Aligned Fe3O4 magnetic nanoparticle films by magneto-electrospray method

“…Owing to the magnetic NPs preference for moving along the eld gradient, the number density distribution of the Fe 3 O 4 NPs along the lm surface could be enhanced by applying a non-uniform magnetic eld. 35 This result emphasizes the alignment of the magnetic moments of the NPs. The application of the magnetic eld during the lm deposition aligned the magnetic moments of the NPs, which increased the H c and M r values of the lm.…”

Toward nanoscale multiferroic devices: Magnetic field-directed self-assembly and chaining in Janus nanofibers

“…[1][2][3] Specifically, multiferroic Janus nanofibers have been of interest recently because their predicted and measured magnetoelectric coupling is higher than bulk thin films. [4][5][6] These fibers couple piezoelectricity and magnetostriction, allowing electrical control of magnetism and vice-versa. 4,[7][8][9] Janus fibers consist of two materials with the interface along the length of the fiber.…”