Syeda Arooj Fatima, R. Shaheen, Amjad Mehmood, Ruzma Riaz, K. Shahzad
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引用次数: 0
Abstract
The effect of Sr2+ doping on electrical conductivity and dielectric constant was studied in Y2 − xSrxNiMnO6 (YSNMO). Rietveld refinement of XRD data showed the coexistence of monoclinic (P21/n) and rhombohedral (R\(\bar 3\)) as major and minor phases, respectively. Impedance analysis of YSNMO was performed to investigate the presence of various electro-active regions, electrical conduction mechanisms and the origin of the colossal dielectric constant in wide temperature (83-303 K) and frequency (40 Hz-6 MHz) ranges. An equivalent circuit model (RgCg)(RgbQgb)(ReQe) has been proposed to correlate the electrical properties. The Rg and Rgb obtained using ZView fitting revealed the semiconducting nature of the sample. The transition in the conduction mechanism from variable range hopping to small polaronic hopping was observed at about 213 K. DC bias measurements, which followed the Mott-Schottky law, confirmed the existence of non-Ohmic electrode contact. The dielectric spectra of ceramic were described using the modified Cole-Cole equation. The frequency dependent ac conductivity was investigated with the Jonscher’s power law.
期刊介绍:
While ceramics have traditionally been admired for their mechanical, chemical and thermal stability, their unique electrical, optical and magnetic properties have become of increasing importance in many key technologies including communications, energy conversion and storage, electronics and automation. Electroceramics benefit greatly from their versatility in properties including:
-insulating to metallic and fast ion conductivity
-piezo-, ferro-, and pyro-electricity
-electro- and nonlinear optical properties
-feromagnetism.
When combined with thermal, mechanical, and chemical stability, these properties often render them the materials of choice.
The Journal of Electroceramics is dedicated to providing a forum of discussion cutting across issues in electrical, optical, and magnetic ceramics. Driven by the need for miniaturization, cost, and enhanced functionality, the field of electroceramics is growing rapidly in many new directions. The Journal encourages discussions of resultant trends concerning silicon-electroceramic integration, nanotechnology, ceramic-polymer composites, grain boundary and defect engineering, etc.