Structural and electrical properties of Ba5SmTi3V7O30 ceramics

Journal of Materials Science Materials in Electronics (Impact Factor: 1.57). 02/2009; 21(2):160-167. 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.

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    • "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]. "
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