Structural and electrical properties of Ba5SmTi3V7O30 ceramics

ArticleinJournal of Materials Science Materials in Electronics 21(2):160-167 · February 2009with2 Reads
Impact Factor: 1.57 · DOI: 10.1007/s10854-009-9887-2

Polycrystalline sample of Ba5SmTi3V7O30 was prepared by a high-temperature solid-state reaction technique. Structural and microstructural characterizations were performed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). X-ray preliminary structural studies reveal that the material has orthorhombic structure at room temperature. Detailed electrical (dielectric and impedance) properties of the material studied by using a complex impedance spectroscopy (CIS) technique in a wide temperature range (33–450°C) at different frequencies (102–106Hz) reveal that the relative dielectric constant of the material increases with rise in temperature and thus bulk has a major contribution to its dielectric and electrical properties. The bulk resistance of the material decreases with rise in temperature exhibiting a typical negative temperature coefficient of resistance (NTCR) behavior. The nature of the temperature variation of conductivity and value of activation energy, suggest that the conduction process is of mixed-type (ionic–polaronic and space charge). The existence of ferroelectricity in the compound was confirmed from polarization study.

    • "It agrees with the decreasing (Fig. S4b) of Z MAX peak heights (proportional to resistance) with increasing temperature. The coincidence of Z at higher frequencies for all temperatures (Fig. S4a) indicates a possible release of space charge [20]. The peaks in the frequency dependence of Z (Figs. 4b and S4b) indicate relaxation in the system. "
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    Full-text · Dataset · Jun 2012
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    No preview · Article · Mar 2012 · Journal of Materials Science Materials in Electronics
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