Augustin, C.O. and Hema, K. and Berchmans, L.J. and Kalaiselvan, R. and Saraswathi, R. (2005) Effect of Ce4+ substitution on the structural, electrical and dielectric properties of NiAl2O4 spinel. Physica Status Solidi A, 202 (6). pp. 1017-1024.

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Abstract

The structural, electrical and dielectric properties of a series of Ni1–xCexAl2O4 (x = 0.0, 0.2, 0.4, 0.6, 0.8) compositions have been studied. The samples were prepared by a novel glycine–nitrate combustion synthesis route. The substitution of Ce4+ for Ni2+ results in an increase in the lattice constant owing to the larger size of the substituent. The X-ray density increases with increasing Ce4+ content. The IR spectra show two fundamental absorption bands, which are shifted gradually towards higher energy with the addition of Ce4+. The UV–visible spectra confirm the preference of Ni2+ for the octahedral site. The dc electrical conductivity increases with increasing temperature due to the mobility of thermally activated charge carriers. Due to the electrostatic screening effect of B-site cations, the conductivity decreases with increasing Ce4+ content. The dielectric constant and loss tangent of the synthesized compounds show the normal behavior of spinel compounds. The ac electrical conductivity increases with increasing applied frequency and decreases with increasing Ce4+ substitution.

Item Type:	Article
Subjects:	Electropyrometallurgy
Divisions:	UNSPECIFIED
Depositing User:	TTBD CECRI
Date Deposited:	17 Jan 2012 05:52
Last Modified:	17 Jan 2012 05:52
URI:	http://cecri.csircentral.net/id/eprint/150

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