Table of Contents
ISRN Materials Science
Volume 2013, Article ID 728195, 10 pages
http://dx.doi.org/10.1155/2013/728195
Research Article

Influence of Nd Substitution by La in on Structural and Transport Properties for Sensing Applications

1Department of Physics, Indian Institute of Technology Hyderabad, ODF Campus, Yeddumailaram, Hyderabad, Andhra Pradesh 502205, India
2School of Physics, University of Hyderabad, Hyderabad, Andhra Pradesh 500046, India

Received 13 December 2012; Accepted 8 January 2013

Academic Editors: V. Baranauskas and V. Ralchenko

Copyright © 2013 Sudarshan Vadnala et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The structural and transport properties of manganites with and 0.2 prepared by solid state reaction route are studied. These compounds are found to be crystallized in orthorhombic structural form. A shift in the metal-semiconductor/insulator transition temperature ( ) towards room temperature (289 K) with the substitution of Nd by La, as the value of is varied in the sequence (0, 0.1, and 0.2), has been provided. The shift in the , from 239 K (for ) to near the room temperature 289 K (for ), is attributed to the fact that the average radius of site-A increases with the percentage of La. The maximum temperature coefficients of resistance (TCR) of ( and 0.2) are found to be higher compared to its parent compound which is almost independent of . The electrical resistivity of the experimental results is explored by various theoretical models below and above . An appropriate enlightenment for the observed behavior is discussed in detail.