Influence of calcination temperature on sol–gel synthesized single-phase bismuth titanate for high dielectric capacitor applications

Abstract

An inexpensive sol–gel combustion method using citric acid as fuel has been used to synthesize bismuth titanate, Bi4Ti3O12 nanopowders. Thermogravimetric analysis proved that a calcination temperature of 900 °C is sufficient for the preparation of single-phase bismuth titanate. X-ray diffraction and Fourier transform infrared spectroscopy are used to examine the influence of calcination temperature on the structural growth of the Bi4Ti3O12 nanopowder. The average crystallite size estimated by using the Scherrer method and the Williamson–Hall method was found to increase with calcination temperature. Photoluminescence behavior as a function of calcination temperature was observed at two different excitation wavelengths of 300 nm and 420 nm. The morphology of the particles analyzed using images obtained from field emission scanning electron microscopy displayed irregular, random sized, and spherical-shaped structures. The stoichiometry and purity of the nanopowder are confirmed by energy-dispersive spectroscopy. The broadband dielectric results established the highest dielectric constant (∊r = 450) for a frequency of 100 Hz achieved with a potential capacitance of 138 pF m−2. This establishes Bi4Ti3O12 as a promising dielectric material for achieving high energy density capacitors for the next-generation passive devices.

Electrical and dielectric behaviors of Al/SiO2-surfactant/n-Si schottky structure in wide range of voltage and frequency

“…The second method for calculating the main electrical parameters of the MS and MIS structures such as n, F , B0 and R s is to utilize the Cheung functions at the high forward bias voltage region, which corresponds to the concave-curvature of ln(I)-V profiles, through the use of the following two-relations [20,21]:…”

A comparison of electrical characteristics of Au/n-Si (MS) structures with PVC and (PVC: Sm2O3) polymer interlayer

“…As can be observed that the N ss profile of MS diode has a maximum value at 4.03×10 13 eV −1 cm −2 while the maximum value of N ss profiles for MPS1 and MPS2 diodes is equal to 6.55×10 12 eV −1 cm −2 and 6.68×10 10 eV −1 cm −2 , respectively. The maximum value of N ss profile for MS diodes is decreased by inserting the PVC and (Sm 2 O 3 -PVC) interfacial layers because of passivating semiconductor surface [36,37].…”

The effect of PVP: BaTiO3 interlayer on the conduction mechanism and electrical properties at MPS structures

“…at the wavelength 440 nm in the UV-Vis absorption spectrum of the barium titanate nanostructure [37,39].…”

“…As can be seen, the maximum value of N ss profile of MS diode is occurred at 9.78×10 13 eV −1 cm −2 while the profile of MPS diode has the maximum of 2.26×10 13 eV −1 cm −2 at valance band energy of 0.45 eV in the considered energy range. Since the presence of the interfacial polymer layer leads to semiconductor surface passivation [38,39], the maximum value of N ss for MPS diode is almost decreased four times respect to MS diode. Also, the current conduction mechanism in both forward and reverse bias of both diodes has been investigated and the effect of the interlayer on the current of free carriers has been compared with each other.…”