Enhancing dielectric properties of barium titanate macrofibers

Abstract

The motivation of this work was to improve the dielectric properties of BaTiO3 (BT) macrofibers by mixing BT nanofibers and commercial BT powder. BT nanofibers were fabricated via electrospinning synthesis. The calcined electrospun nanofibers were chopped and mixed with BT powder and converted in to a thermoplastic feedstock for extrusion of ceramic macrofibers with a diameter of 500 μm. The electromechanical properties of the BaTiO3 macrofibers were investigated by varying calcination temperature of the nanofibers. For both nano and macro fibers, microstructure and phase composition was investigated by SEM and XRD. It could be observed that an increase in calcination temperature of the nanofibers enhanced the final electromechanical properties of the sintered macrofibers. The relative permittivity increased almost twice, the remanent polarisation increased about 4 times and the strain almost increased 10 times with the addition of calcined nanofibers to macrofibers.

BaTiO3 nanotubes by co-axial electrospinning: Rheological and microstructural investigations

“…Thermogravimetry analysis (TGA) coupled with differential scanning calorimetry (DSC) was performed on green fibers with heating rate of 2 °C/min under air atmosphere from 50 to 1000 °C using a NETZSCH STA 449F3 (Netzsch, Germany). To investigate the DSC peaks, thermal analysis with the same conditions was also done on a sample of electrospun BT nanofibers (NFs) prepared according to the another work [50]. For the preparation of NFs, the co-axial spinneret was not used.…”

“…Using the shell solution comprising 50 vol% of 7.8 wt% PVP solution (sol 1), the jet was unstable and no mat was formed during the co-axial electrospinning. However, using this solution, BT NFs could be successfully prepared by single capillary electrospinning [50]. Generally, during a co-spinning process, the elongation of the shell is mainly created by electrostatic repulsions between the surface charges.…”

“…There are several reports on synthesizing BT nanofibers by electrospinning technique for use in different applications [33,[45][46][47][48][49]. Previously, at Empa, electrospinning has been successfully utilized to produce BT [50] and other different ceramic nanofibers [31,32,[51][52][53][54]. However, there are not many reports on fabrication of BT NTs by electrospinning specially using co-axial technique.…”

High dielectric thin films based on barium titanate and cellulose nanofibrils

“…[4][5][6][7] Ferroelectric ceramics such as lead-free barium titanate (BaTiO 3 , BTO) have long been of interest as llers for high dielectric composites. 8,9 This is due to their high dielectric constant (as high as 7000), 10 low dissipation, impressive piezoelectric and pyroelectric properties. 11,12 The effects of size, shape (e.g., nanoparticles, nanorods, nanowires, nanocubes), crystal phase (e.g., cubic, tetragonal, orthorhombic, rhombohedral), matrix, surface conditions, porosity, ller loading and distributions have been discussed intensively in the literature.…”

Synthesis of BaTiO3 nanoparticles as shape modified filler for high dielectric constant ceramic–polymer composite

“…6 BaTiO 3 (BT) is of particular interest due to its perovskite structure and high dielectric constant of more than 1000, which is signicantly higher than other ceramics, for example, 3.9 for SiO 2 . 7,8 BT is used in elds requiring high piezoelectricity and high dielectric constants because of its polarization inversion and high dielectric constant. 9 However, the material for the insulating layer needs to be exible and stretchable in order to grab the various shaped objects.…”