Dielectric and Transport Properties of Strontium Modified Calcium Copper Titanate

Abstract

The present article provides the detailed study of the effect of strontium on the structural, microstructural, dielectric and electrical characteristics of calcium copper titanate (i.e. Ca_0.95Sr_0.05Cu₃Ti₄O₁₂, referred as CSCTO further) synthesized by a cost-effective ceramic processing technology. The structural analysis carried out suggests a cubic symmetry in the prepared sample. The dielectric relaxation and electrical conduction mechanism of CSCTO were studied using various powerful spectroscopic tools (i.e dielectric and impedance). Study of temperature dependence of dielectric permittivity exhibits very high (giant) dielectric permittivity (5 $\times$ 10³) and low loss factor at low frequency (1 kHz) at an intermediate temperature (315 °C). Structure–properties relationship and conduction mechanism have been studied in a wide frequency (10³–10⁶ Hz) and temperature (25–315 °C) range. At region of low frequency and high temperatures, there is a dominant role of the interface and Maxwell–Wagner dielectric relaxation mechanism in CSCTO bulk ceramic. The grain, grain boundary and electrode contributes towards the capacitive and resistive property of the sample are discerned from Nyquist plot. The ferroelectric (P–E) loop of the sintered CSCTO bulk sample at room temperature showed a lossy hysteresis loop. These findings further promote the capabilities of CSCTO as a base for supercapacitor.

Keywords:

• X-Ray diffraction
• microstructure
• ferroelectric phase
• supercapacitor
• dielectric properties

Acknowledgements

Miss Madhusmita Sahu likes to thanks the Director, IMS Bhubaneswar for some experimental help. Miss Madusmita Sahu fabricated the sample and characterize it. Mr Sugato Hajra contributed towards analysis and writing the article. Dr RNP Choudhary supervised the work.

Disclosure statement

No potential conflict of interest was reported by the authors.