Thesis Submitted

Mrs. S. V. Meenakshi

Sri Meenakshi Govt. Arts College for Women (Autonomous) Madurai 625 002,
Mobile: 90801 49901,
Email: svmeenu74@yahoo.in

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:

1.
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). 
2.
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).
3.
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),
4.
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)
5.
Communicated

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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