Dr. N. Thenmozhi

Dr. N. Thenmozhi, Associate Professor, PG and Research Department of Physics,
N.M.S.S. Vellaichamy Nadar College, Nagamalai, Madurai-625 019
Mobile: 98429 69355,
Email: [email protected]

Ph.D. Topic:

Growth, Physical and X-ray Characterization of Manganite Structures

Date of Regis: 16.07.2009
Reg. No. P8479
Viva-Voce date: 13.04.2018

Introduction:
The work investigates the growth, physical and X-ray characterization of samples having manganite structures. Manganite structured materials have mixed valence system with perovskite structure denoted as R1-xAxBO3, (R-Rare-earth cations (La, Pr, Nd, Sm, Eu, Gd ), A- Alkaline earth cations (Ca, Sr, Ba) and B-Transition metal cations (Cr, Mn, Sc, Ni, Fe)). Some of the manganite structured materials are orthochromites, orthomanganites, orthoferrites, orthonickelates and orthoscandates. The manganite structured materials viz.,

(Co, Mn) doped (La, Ca) based chromites – (La0.8Ca0.2)(Cr0.9-xCo0.1Mnx)O3                            

(Co, Fe) doped (La, Ca) based chromites –  (La0.8Ca0.2)(Cr0.9-xCo0.1Fex)O3                                         

(Co, Cu) doped (La, Ca) based chromites – (La0.8Ca0.2)(Cr0.9-xCo0.1Cux)O3

La1-xCaxMnO3 manganites

La1-xSrxMnO3 manganites

The surface morphology and microstructure of the synthesized samples have been examined using scanning electron microscope (SEM). The elemental compositions of the materials have been identified qualitatively and quantitatively using energy dispersive X-ray spectroscopy (EDS). Optical band gaps (Eg) of the materials have been estimated by UV-visible absorption spectra using Tauc plot. The magnetic properties of the materials have been analyzed by vibrating sample magnetometer (VSM) measurements.Materials interest:

List of Publications:

Ceramic materials, semiconductors and magnetic materials have been synthesized using high temperature solid state reaction method. To study the structural properties, the prepared samples have been characterized by powder X-ray diffraction (PXRD) technique and analyzed using Rietveld method. The execution of Rietveld method was carried out by the software JANA 2006. The charge density distributions between the atoms in the crystal lattice and bonding features have been analyzed using maximum entropy method (MEM). MEM charge density distribution in the unit cell has been visualized through the software VESTA.

1. R. Saravanan, N. Thenmozhi, Yen-Pei Fu,
Structural characterization and electron density distribution studies of (La0.8Ca0.2)(Cr0.9-xCo0.1Mnx)O3,                                                                                                                                                  Physica B: Physics of Condensed Matter, 493 25-34 (2016) (Elsevier Publication) (Impact Factor: 1.386)      2. R. Saravanan, N. Thenmozhi, Yen-Pei Fu,
Preparation and charge density in   (Co, Fe) - doped La-Ca-based chromite,                                      Journal of Electronic Materials, 45 4364-4374 (2016) (Springer Publication) (Impact Factor: 1.579)                3. N. Thenmozhi, R. Saravanan, Yen-Pei Fu,
Crystal structure and bonding analysis of (La0.8Ca0.2)(Cr0.9-xCo0.1Cux)O3 ceramics,              Zeitschrift für Naturforschung A- A Journal of Physical Sciences, DOI: 10.1515/zna-2016-0474 (De Gruyter Publication) (Published online) (Impact Factor: 1.432)                                                                            4. N. Thenmozhi, S. Sasikumar, S. Sonai, R. Saravanan,
Electronic structure and chemical bonding in La1-xSrxMnO3 perovskite ceramics,                      Materials Research Express, 4 (2017) 046103 1-11 DOI.org/10.1088/2053-1591/aa6abf (IOP Publication) (Published online) (Impact Factor:1.068)                                                                                                                5. N. Thenmozhi, R. Saravanan,
High temperature synthesis and electronic bonding analysis of Ca-doped LaMnO3 rare-earth manganites,                                                                                                                                                                Rare Metals, DOI 10.1007/s12598-017-0964-z (Springer Publication) (Published online) (Impact Factor: 1.189)                                                                                                                                                                                6. N. Thenmozhi, S. Sasikumar, R. Saravanan, Yen-Pei Fu,
Study of charge density and crystal structure of co-doped LaCrO3 system,                                 Mechanics, Materials Science & Engineering, 9 (2017) DOI: 10.2412/mmse.99.30.568 (Magnolithe GmbH Publication) ISSN: 2412-5954 (Published online) (Impact Factor: 0.12)                                                                7. N. Thenmozhi, R. Saravanan, Yen-Pei Fu,
Effects of cations substitution on structural and magnetic properties of LaCrO3 ceramic perovskites,  Novel ceramic materials, Chap.4, Materials Research Forum LLC, Materials Research Foundations, USA, 2 40-54 (2016) ISBN 13: 978-1-945291-02-9                                                                                                      8. N. Thenmozhi, R. Saravanan,
Synthesis, Structure and Magnetic Behavior of Ce-Doped Lanthanum Manganite Ceramics,                  Novel ceramic materials, Chap.13, Materials Research Forum LLC, Materials Research Foundations, USA, 2 177-189 (2016) ISBN 13: 978-1-945291-02-9