Thesis Submitted

Mrs. S. V. Meenakshi

Ms. S.V. Meenakshi

Sri Meenakshi Govt. Arts College for Women (Autonomous) Madurai 625 002,
Mobile: 90801 49901,

Ph.D. topic: Synthesis and structural, dielectric, magnetic characterization of ceramic-ferrite magneto-electric composites
Date of Registration : 21/11/2014
Date thesis submitted: 23/02/2022

Introduction about Ph.D. work:

The main objective of this work is the preparation and structural characterization of ceramic-ferrite magneto electric composites. At present (1-x)BaTiO3+xCoFe2O4 and (1-x)BaTiO3+xMgFe2O4 have been synthesized by conventional high temperature solid state reaction method using tubular furnace. The prepared samples have been characterized using powder X-ray diffraction (PXRD) and analyzed using the powder profile refinement technique by adapting the software JANA 2006, to examine the structural properties. Effects of various compositions of ferroelectric and ferrite on the internal electronic structure, chemical bonding and charge density distribution are examined through maximum entropy method (MEM) by using PRIMA and VESTA. Optical band gap (Eg) values are evaluated using UV-visible spectrophotometry (UV-vis). Microstructure and surface morphology are analyzed using scanning electron microscopy (SEM). Elemental compositions of the prepared ceramic systems are studied qualitatively and quantitatively by energy dispersive X-ray spectroscopy (EDS). My PhD work is going on and still there are two series to be synthesized and studied.

Materials interest: Ceramics, ferrites, ferroelectric materials, Multiferroic materials

  1. (1-x) BaTiO3+ x CoFe2O4
  2. (1-x) BaTiO3+ x NiFe2O4
  3. (1-x) BaTiO3+ x ZnFe2O4
  4. (1-x) BaTiO3+ x MgFe2O4

List of Publications:

Inter Bond Experimental Electron Density in Magnesium Ferrite
Ceramic (MgFe2O4) Through XRD,
M.J. Viswanath, M. Aysha kani, S.V. Meenakshi and R. Saravanan,
Materials Research Forum, Materials Research Foundations, USA,
Vol.2 (Novel Ceramic Materials), Ch.3, 27-39, (2016). 
Synthesis and Characterization of Al2TiO5-TiO2-Al2O3 Ceramics: Correlation with
Charge Density,
S.V. Meenakshi, R. Saravanan,
Novel Ceramic Materials,Materials Research Forum,
Materials Research Foundations, USA,
Vol.2 (Novel Ceramic Materials), Ch.7, 81-92,(2016).
Charge Density Analysis, Structural, Electrical and Magnetic Studies of 
(1-x)BaTiO3+NiFe2O4 Ceramic Composite,
S.V. Meenakshi, R. Saravanan, N.Srinivasan, O.V.Saravanan, D.Dhayanithi, and
Nambi Venkatesan Giridharan,
J.Electronic Materials(Springer),49,7349–7362 (2020)
DOI: 10.1007/s11664-020-08481-4
(Impact Factor= 1.774),
Exploration of (1 - x) BaTiO3 + x ZnFe2O4 magneto-electric ceramic composite on 
charge density: Structure and its characterization
S.V. Meenakshi, R. Saravanan, N. Srinivasan, D. Dhayanithi, N.V.Giridharan
Journal of Alloys and Compounds (Elsevier), 888, 161491 (2021)
(Impact Factor= 5.316)

Magneto-electric ceramic composite materials

Devices made of Magneto electric (ME) materials are one of the highest priority research topic to develop the next generation of novel multifunctional materials. These systems show the simultaneous existence of two or more ferroic orders, and cross-coupling between them, such as magnetic spin, polarisation, ferroelastic ordering, and ferro toroidicity. Based on the type of ordering and coupling, there is a wide variety of device applications, such as magnetic field sensors, nonvolatile memory elements, ferroelectric photovoltaics, nano-electronics etc. Since single-phase materials exist rarely in nature with strong cross-coupling properties, intensive research activity is being pursued towards the discovery of new single-phase multiferroic materials and the design of new engineered materials with strong magneto-electric (ME) coupling investigated by the scientific ferroics community to develop the next generation of novel multifunctional materials.  The ceramic material BaTiO3 will be having the dielectric properties which are very useful in a variety of applications. It is a well known dielectric, piezoelectric, ferroelectric material. Ferrites like, CoFe2O4, NiFe2O4, ZnFe2O4, and MgFe2O4 are very useful magnetic materials having variety of applications. They are used in transformer cores, they have low coercivity, high permeability and ferrite cores used for signals have a range of applications from 1 kHz to 300 MHz. Composites of ceramic-ferrites synthesized to enhance the ferroelectric and magnetic properties in a single material. The characterizations (XRD, P-E, M-H, UV-Vis, SEM, EDX, Magnetocapacitance) of the prepared sample gives the nature of the behavior of sample prepared.

Materials interest:

Ceramics, ferrites, ferroelectric materials, Multiferroic materials

  1. (1-x) BaTiO3 + x CoFe2O4
  2. (1-x) BaTiO3 + x NiFe2O4
  3. (1-x) BaTiO3 + x ZnFe2O4
  4. (1-x) BaTiO3 + x MgFe2O4

Name: Mr. T. Akilan, M.Sc., M.Phil.

Mr. T. AKILAN, M.Sc., M.Phil.

(Now working at UAE - Abu Thabi)
Project Fellow-UGC Major Research Project
PG and Research Department of Physics
Thiagarajar College of Arts and science
Teppakulam, Madurai-625 009
Mobile: 94898 65653

Dr.N.Srinivasan (Supervisor) PG and Research Department of Physics Thiagarajar College of Arts and science Teppakulam, Madurai-625 009 Ph.D. Topic: SYNTHESIS AND LOCAL STRUCTURAL CHARACTERIZATION OF OXIDE BASED DILUTE MAGNETIC MATERIALS

Date of Registration :  03/10/2011
Registration no. : F8754
Date of Thesis submission:  23/12/2022
Date of viva voce examination :

Introduction about Ph.D. work:

O-DMS (Oxide based DMS) materials have created interest due to the possibility of inducing room temperature ferromagnetism. O-DMS materials are essential materials in spintronic devices. The study of local structural fluctuation and electron density distribution may help in imminent understanding the nature of bonding and charge transfer etc. The results of localized structure of the material with varying dopant concentration may pave way for new spintronic devices.The main objective of this work is to investigate the growth, physical and X-ray characterization of samples having room temperature ferromagnetism and semiconducting properties. The growth of ZnO doped with transition metals like V, Ni, Fe and Ti and mixed systems (possibility of RT FM) has been accomplished. Melt growth technique has been used. Solid state reaction technique offers several advantages such as low cost, easy controlling of the total dopant amounts, and facility of producing bulk amounts of materials. The growth has been accomplished using a well-planned temperature control programme. The quality of the grown samples have been checked by X-ray methods. The impurity levels have been  estimated using SEM/EDAX (Energy Dispersive Analysis of X-rays). Powder X-ray data – to study structural changes have been used to determine the compositions of the dopant atoms. The magnetic susceptibility measurements, M Vs H, M Vs T to analyze the AFM, FM transitions have been done.
Optical band gap studies have been  undertaken in-order to measure the optical properties of ZnO.

Materials interest:
Zinc oxide, semiconductors, transition metal ions

  • Zn1-xTixO (x=0.02, 0.03)
  • Zn1-xFexO (x = 0.02, 0.04, 0.06)
  • Zn1-xVxO (x=0.02, 0.04, 0.06)
  • Zn1-xNix/2Vx/2O (x=0.02, 0.04, 0.06)

Journal Publications: International: 5;

National: Nil Conference/Seminar : 3

Status:  Work completed

List of Publications: 

1. Structure of vanadium doped zinc oxide, Zn1-xVxO,
T. Akilan, N. Srinivasan, R. Saravanan, Prasanta Chowdury,
Materials and Manufacturing process, Taylor & Francis, 29:7, 780-788 (2014)
(Impact Factor: 4.616) 

2. Structure analysis of Ni and V co- doped zinc oxide prepared by solid state reactions,
T. Akilan, N. Srinivasan, R. Saravanan 
Journal of material science : Materials in electronics, 25,2898–2904(2014)
(Springer Publications) 
(Impact Factor: 2.478)

3. Magnetic and optical properties of Ti doped ZnO prepared by solid state reaction,
T. Akilan, N. Srinivasan, R. Saravanan
Material science in semiconductor processing, 30, 381 - 187(2015)
(Elseveir Publication) 
(Impact Factor: 3.927) 

4. Structural and magnetic studies on Fe doped zinc oxide, Zn1-XFexO synthesized
by solid state reaction,
T. Akilan, N. Srinivasan, R. Saravanan, 
Journal of material science : Materials in electronics, 26,9882–9890(2015)
(Springer Publications) 
(Impact Factor: 2.478)
List of Conferences Attended
1. International Conference on Recent Trends in Advanced Materials – 
Oral Presentation held at VIT University, Vellore during 20-22, February 2012
T. Akilan, N. Srinivasan., R. Saravanan,

2. International conference on Advanced Materials, Processing and Devices
held on 15-16, July 2013 at the department of Material Science, Madurai Kamaraj 
Univeristy, Madurai.
T. Akilan, N. Srinivasan., R. Saravanan,

3.  International Conference and workshop on Nanostructure ceramics and other 
nano materials held on 13-16, New Delhi, March 2012 – Abstract has been published
T. Akilan , N. Srinivasan , R. Saravanan