Facile preparation of uniform barium titanate (BaTiO₃) multipods with high permittivity: impedance and temperature dependent dielectric behavior

Abstract

Perovskite barium titanate (BaTiO 3 ) multipods were prepared via high temperature solid state reaction. The crystal structure and morphology of BaTiO 3 particles were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), and scanning probe microscopy (SPM). The XRD analysis of the crystal structure revealed that a single-phase compound was formed having tetragonal crystal structure. Calorimetric study (DSC) over room to high temperature was used to find the energy involved in different steps of synthesis especially during the initiation and the termination process for the formation of BaTiO 3 . These multipods have high average aspect ratio ($10, where average diameter $300 nm and average length $3 mm) as seen from FESEM. UV-Vis spectroscopy reveals that the prepared material is UV active. The bulk and surface chemical composition of these BaTiO 3 particles as investigated by Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) spectra reveals that in the prepared BaTiO 3 , the titanium ions exist in two different oxidation states, namely Ti 3+ and Ti 4+ . The BaTiO 3 multipod exhibits high permittivity with relatively low dielectric loss. From impedance analysis of the material, the dual resistivity characteristics, one for grain and the other for grain-boundary can be distinguished. An equivalent circuit has been proposed through analysis of the complex impedance plot (Nyquist plot) for BaTiO 3 multipods. This material has perfect capacitative nature as seen from the Bode plot, and can be used for charge storage devices and other electronic applications. From temperature dependent dielectric analysis, the Curie temperature of BaTiO 3 multipods is found to be $85 C.

High capacitive amorphous barium nickel phosphate nanofibers for electrochemical energy storage

“…The peak positions and binding energy gap between the two signals clearly demonstrate the existence of Ba 2+ . [39][40][41] Moreover, the HRXPS spectra in 42 During the process of fabrication of Ba x Ni 3Àx (PO 4 ) 2 nanober, we noticed that the content of precursor Ni(NO 3 ) 2 plays a key role in the formation of nanobers. Fig.…”

Polydimethylsiloxane–PbZr0.52Ti0.48O3 nanocomposites with high permittivity: Effect of poling and temperature on dielectric properties

“…The incorporation of electroceramic filler particles in the polymer matrix have attracted great attention of many researchers due to their promising applications such as flexible electronics, temperature/pressure sensor, actuators, and hydrophones . Polymer–ceramic composites carry the combined properties of the polymer matrix (low density, flexibility, low processing temperature, and good mechanical strength) and ceramic filler (brittle, good pyroelectric, and piezoelectric properties) . These composites are good materials for embedded capacitors in organic substrates as they have low processing temperature of polymers and high permittivity of ceramics .…”

Lattice-based Monte Carlo simulations of the electrocaloric effect in ferroelectrics and relaxor ferroelectrics

“…Based on first-principles results with zero strain and no non-soft-mode eigenmode amplitudes [34], the coefficients a = 13.7128 × 10 8 J m C −2 , b = 28.908 × 10 9 J m 5 C −4 are used in the Landau energy, while the sixth-order term is ignored. Different values of the high-frequency permittivity r are given in literature, varying from 6.0 to 15.0 [35][36][37]. In the following simulations, we choose r = 12.0.…”