| | | | | | | |
                
Indian Science Technology and Engineering facilities Map
Supplier Map
Service Map










Publications

Publication Details

Applicant:
Central University of Tamil Nadu 
Author:
A. R. Jayakrishnan, Kevin V. Alex, Athul Thomas, J. P. B. Silva, K. Kamakshi, Navneet Dabra, K. C. Sekhar, J. Agostinho Moreira, M. J. M. Gomes 
Corresponding Authors:
J. P. B. Silva, K. C. Sekhar 
DOI #:
https://doi.org/10.1016/j.ceramint.2018.11.250 
Title:
Composition-dependent xBa(Zr0.2Ti0.8)O3-(1-x)(Ba0.7Ca0.3)TiO3 bulk ceramics for high energy storage applications 
Journal:
Ceramics International 
Year:
2019 
Volume:
45 
Page:
5808 - 5818 
Keywords:
Energy storage capacitors, Lead free ceramics, Spontaneous polarization, Fatigue, Dielectric constant, Raman spectroscopy 
Abstract:
This work reports the composition dependent microstructure, dielectric, ferroelectric and energy storage properties, and the phase transitions sequence of lead free xBa(Zr0.2Ti0.8)O3-(1-x)(Ba0.7Ca0.3)TiO3 [xBZT-(1-x)BCT] ceramics, with x = 0.4, 0.5 and 0.6, prepared by solid state reaction method. The XRD and Raman scattering results confirm the coexistence of rhombohedral and tetragonal phases at room temperature (RT). The temperature dependence of Raman scattering spectra, dielectric permittivity and polarization points a first phase transition from ferroelectric rhombohedral phase to ferroelectric tetragonal phase at a temperature (TR-T) of 40 °C and a second phase transition from ferroelectric tetragonal phase - paraelectric pseudocubic phase at a temperature (TT-C) of 110 °C. The dielectric analysis suggests that the phase transition at TT-C is of diffusive type and the BZT-BCT ceramics are a relaxor type ferroelectric materials. The composition induced variation in the temperature dependence of dielectric losses was correlated with full width half maxima (FWHM) of A1, E(LO) Raman mode. The saturation polarization (Ps) ≈8.3 μC/cm2 and coercive fields ≈2.9 kV/cm were found to be optimum at composition x = 0.6 and is attributed to grain size effect. It is also shown that BZT-BCT ceramics exhibit a fatigue free response up to 105 cycles. The effect of a.c. electric field amplitude and temperature on energy storage density and storage efficiency is also discussed. The presence of high TT-C (110 °C), a high dielectric constant (εr ≈ 12,285) with low dielectric loss (0.03), good polarization (Ps ≈ 8.3 μC/cm2) and large recoverable energy density (W = 121 mJ/cm3) with an energy storage efficiency (η) of 70% at an electric field of 25 kV/cm in 0.6BZT-0.4BCT ceramics make them suitable candidates for energy storage capacitor applications. 
Entered by:
Koppole Chandra Sekhar on 2020-09-02 
 
THE VISION
THE MISSION
ABOUT I-STEM
It has always been the basic tenet of the Government of India, in generously funding R&D efforts at academic institutions over the years, that facilities established through such support be made available to those needing them and qualified to make use of them for their own research work
read more >>

However, this was never easy or straightforward for, among other reasons, there was no ready source of information of what facility was available and where. Thanks to the Web, it is much easier today to have a national and regional “inventory of resources”, so as to match users with the resources they need, and to do all this in an efficient and transparent manner.

This can lead to a leap in R&D productivity and greatly enhance the effectiveness of public investment. This is the motivation behind I-STEM.
read less <<
Visitor Hit Counter
Toll Free Number : 1800 425 3281
Hosted at Indian Institute of Science
Copyright © 2019 I-STEM. All rights reserved    Audited by: STQC Bengaluru.