Structural, Thermal and Electrical Property of Polycrystalline LaLiMo₂O₈

Sanjaya Brahma, Ram Naresh Prasad Choudhary, Awalendra Kumar Thakur, Srinivasarao Ajjampur Shivashankar

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DOI: 10.4236/njgc.2012.21002                

Abstract

This research article reports electrical characterization of a rare earth molybdate based on combination of rare earth (La⁺³) and alkali (Li⁺) metal ions. The experimental observation suggests the negative temperature coefficient of resistance behavior of the material. The material has been prepared by standard solid state reaction method, where the synthesis conditions have been optimized by thermal analysis. A possible mechanism for the formation of the polycrystal-line LaLiMo₂O₈ is reported. A systematic analysis has been done to determine the crystal structure of the powder material and it was found that the powder material was crystallized to tetragonal unit cell structure. Electrical properties have been studied using a.c. impedance measurement. The temperature variation of electrical conductivity of the material shows typical Arrhenius behavior. The activation energy evaluated from conductivity data works out to be ~0.94 ev.

Keywords

Powders; Solid State Reaction; X-Ray Methods; Thermal Properties; Electrical Properties

Conflicts of Interest

The authors declare no conflicts of interest.

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