Influence of Nd Substitution by La in Nd0.7Sr0.3MnO3 on Structural and Transport Properties for Sensing Applications. (21st February 2013)

• Record Type: Journal Article
• Authors: Vadnala, Sudarshan; Asthana, Saket; Pal, Prem; Srinath, S.
• Other Names: Baranauskas V. Academic Editor.; Ralchenko V. Academic Editor.
• Is Part Of: ISRN materials science. Volume 2013(2013)
• Publication Date: 2013-02-21
• Subjects: Materials science -- Periodicals; Materials science; Periodicals; 620.11
• DOI: 10.1155/2013/728195
• Languages: English
• ISSNs: 2090-6080

Abstract

Abstract : The structural and transport properties ofNd 0.7 - x La x Sr 0.3 MnO 3 manganites withx = 0, 0.1, 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 (T MI ) towards room temperature (289 K) with the substitution of Nd by La, as the value ofx is varied in the sequence (0, 0.1, and 0.2), has been provided. The shift in theT MI, from 239 K (forx = 0 ) to near the room temperature 289 K (forx = 0.2 ), is attributed to the fact that the average radius〈 r A 〉 of site-A increases with the percentage of La. The maximum temperature coefficients of resistance (TCR) ofNd 0.7 - x La x Sr 0 .3 MnO 3 (x = 0.1 and 0.2) are found to be higher compared to its parent compoundNd 0 .7 Sr 0 .3 MnO 3 which is almost independent of〈 r A 〉 . The electrical resistivity of the experimental results is explored by various theoretical models below and aboveT MI . An appropriate enlightenment for the observed behavior is discussed in detail.