Dr. S. AYYAPPAN. : Mobile Number : / :

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1 Dr. S. AYYAPPAN ayyappansathya@gmail.com Mobile Number : / Web page : Sex : Male Date of Birth : 4 th June 1981 Marital Status : Single Residential Address : # 319, Chittoor road, Amirthapuram, Tiruttani , Tamil Nadu, India ACADEMIC QUALIFICATIONS Ph.D. Physics, Indira Gandhi Centre for Atomic Research, Kalpakkam, India. (Degree awarded by University of Madras, India) Thesis Title: High Temperature Phase Transition Studies in Spinel Ferrite Nanoparticles M. Phil., Nuclear physics, Department of Nuclear physics, University of Madras. (Marks obtained: %) Project Title: Comparative Studies on Zn0.95Ni0.05O DMS Synthesized by co-precipitation and Ceramic Methods M.Sc., Physics, Presidency college, University of Madras. (Marks obtained: %) B.Sc., Physics, Presidency college, University of Madras. (Marks Obtained: %) Nov Sep June 2003 July 2001 TEACHING EXPERIENCE Nov March 2012 Resource person for the high school science teachers training program at the talent development centre, Indian Institute of Science (Kudapura campus), Bangalore. Oct May 2005 Taught physics courses and conduct the physics experiments for the under graduate students of Government Arts and Science College, Tiruttani. RESEARCH EXPERIENCE Research Associate March 2011 Sep Department of Physics, Indian Institute of Science, Bangalore, India. Organic thin films: Preparation of organic thin films of lipid bilayer membrane using Langmuir-Blodgett technique and studied the morphology using atomic force microscopy.

2 Research scholar May Nov 2010 Indira Gandhi Centre for Atomic Research, Kalpakkam, India. Magnetic nanoparticles: Preparation of size controlled iron oxide nanoparticles using precipitation method. Growth mechanism of CoFe2O4 nanoparticles, formation impurity and its influence in magnetic property also studied systematically. Various spinel ferrites MFe 2 O 4 (M = Mn, Fe, Co, Zn) nanoparticles are also prepared and studied its structural, thermal and magnetic properties. Bistable switching behavior and room temperature magnetic ordering is achieved in ZnFe 2 O 4 nanoparticles. Magnetic nanofluids (Ferrofluids): Synthesis of oil and water based magnetic nanofluids. Structural phase transition studies of ferrofluids under different annealing conditions are carried out systematically. Initial size and influence of annealing atmosphere on structural reduction of ferrofluid is studied. Department of Nuclear Physics, University of Madras, India. M.Phil., Aug Oct 2004 Dilute Magnetic Semiconductor material: Zn0.95Ni0.05O was prepared using chemical and ceramic methods and its structural and magnetic properties were studied. A weak ferromagnetism is achieved at room temperature, which could be suitable for spintronic applications RESEARCH INTERESTS Synthesis and characterization of magnetic nanomaterials and nanofluids Applications of nanomaterials and nanofluids (Biomedical, Sensors, Energy materials, Rheology, Transport properties of nanofluids, etc.) Shape and size dependent physical properties of nanomaterials Nanostructured magnetic, semiconductor and multiferroic Nanostructured magnetic - polymer thin films EXPERIMENTAL SKILLS Chemical synthesis method: Wet chemical, sonochemical, solvothermal, microemulsion method and Langmuir-Blodgett. Characterization techniques: In-situ X-ray diffraction; Vibrating Sample Magnetometer (VSM); SQUID; Mössbauer spectroscopy; Micro Raman spectroscopy; Thermo-gravimetric analysis coupled mass spectra; Fourier Transform-Infrared (FTIR) spectroscopy; Dynamic light scattering (DLS); UV Visible spectroscopy and Atomic force microscopy. Data analysing and graphing software: ORIGIN, Microsoft office, Labview and Matlab 2

3 AWARDS Qualified Graduate Aptitude Test for Engineers (GATE) 2004, organized by Indian Institute of Technology (IIT) Delhi Awarded Junior Research Fellowship by Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam Award of research associate by the department of physics, IISc, Bangalore PUBLICATIONS IN PEER-REVIEWED INTERNATIONAL JOURNALS 1 D. Paul Joseph,, C. Venkateswaran Comparative Studies on Zn0.95Ni0.05O DMS Synthesized by co-precipitation and Ceramic Methods J. Alloys Compd. 415 (2006) G. Gnanaprakash,, T. Jayakumar, John Philip and Baldev Raj Magnetic Nanoparticles with Enhanced γ-fe2o3 to α-fe2o3 Phase Transition Temperature Nanotechnology 17 (2006) , G. Gnanaprakash, G. Panneerselvam, M.P. Antony, and John Philip Effect of Surfactant Monolayer on Reduction of Fe3O4 Nanoparticles under Vacuum J. Phys. Chem. C 112 (2008) , John Philip, and Baldev Raj A Facile Method to Control the Size and Magnetic Properties of CoFe2O4 Nanoparticles Mater. Chem. Phys. 115 (2009) , John Philip, and Baldev Raj Effect of Digestion Time on Size and Magnetic Properties of Spinel CoFe2O4 Nanoparticles J. Phys. Chem. C 113 (2009) , S. Mahadevan, P. Chandramohan, M. P. Srinivasan, John Philip and Baldev Raj Influence of Co 2+ ion concentration on the size, magnetic properties and purity of CoFe2O4 spinel ferrite nanoparticles J. Phys. Chem. C 114 (2010) , S. Philip Raja, C. Venkateswaran, John Philip and Baldev Raj Room Temperature Ferromagnetism in vacuum annealed ZnFe2O4 nanoparticles App. Phys. Lett. 96 (2010) , G. Panneerselvam, M. P. Antony and John Philip Structural Stability of ZnFe2O4 Nanoparticles under Different Annealing Conditions Mater. Chem. Phys. 128 (2011) , G. Panneerselvam, M. P. Antony, John Philip and Baldev Raj Facile Reduction of CoFe2O4 Nanoparticles under Vacuum Annealing Mater. Chem. Phys. 130 (2011) , G. Panneerselvam, M. P. Antony, N. V. Rama Rao, N. Thirumurugan, A. Bharathi and John Philip Effect of initial particle size on phase transformation temperature of surfactant capped Fe3O4 nanoparticles J. Appl. Phys. 109 (2011)

4 OTHER PUBLICATION 1. Role of Surfactant Monolayer on Phase Transitions in Spinel Ferrite Nanoparticles during Vacuum Annealing IGC News Letter. 84 (2010) 14 CONFERENCE PRESENTATIONS INTERNTIONAL 1. G. Gnanaprakash,, S. Mahadevan, T. Jayakumar, P. Kalyanasundram, J. Philip and B. Raj Effect of digestion time on nano-particle growth during coprecipitation Eighth International Conference on Nanostructured Materials (NANO) , G. Gnanaprakash, John Philip and Baldev Raj Effect of solubility product on ferrite nanoparticle size International conference on Nanoscience and Nanotechnology (ICNSNT) , G.Gnanaprakash & John Philip Solvent Polarity Effect On CoFe2o4 Nanoparticles Formation During Co-Precipitation Technique International conference on magnetic materials (ICMM) , G. Gnanaprakash, S.Mahadevan & John Philip Effect of solvent polarity on magnetic properties of Fe3O4 nanoparticles. International Conference on Nano Science and Technology (ICONSAT)-2008 NATIONAL 1., G. Gnanaprakash and John Philip Growth of Fe3O4 Nanoparticles in Presence of Magnetic Field National conference on Smart Materials and Recent Technologies (SMART) and J. Philip Effect of surfactant monolayer on reduction of Fe3O4 nanoparticles under vacuum 53rd DAE Solid State Physics Symposium (DAE-SPS) 2008 WORKSHOP/SCHOOL Participated in DST Advanced School on Nanoscience and Nanobiology, Organized by Indian Institute of Science, Bangalore,

5 A SHORT STATEMENT OF PREVIOUS RESEARCH EXPERIENCE M.Phil. Research work in Spintronics: [Publication: 1] Effect of Ni substitution on structural and magnetic properties of ZnO nanoparticles prepared by co-precipitation and ceramic methods were studied. Zn0.95Ni0.05O exhibits a weak ferromagnetic behavior around room temperature. Ph.D. Research Work in Spinel Ferrite Nanoparticles: [Publications: 9] My Ph.D thesis titled high temperature phase transition studies in spinel ferrite nanoparticles deals with the optimization of synthesis parameters for producing pure and stable magnetic nanofluids (ferrofluids) using precipitation method. Further, attempts are made to study the phase transition and magnetic properties of spinel ferrites under various annealing conditions. The very important results obtained during the course of my research work are as follows: Established new methodologies for the production of phase pure MFe2O4 (M = Mn, Fe, Co and Zn) nanoparticles using precipitation technique Demonstrated room temperature ferromagnetism in vacuum annealed ZnFe2O4 nanoparticles Obtained the first experimental evidence for surfactant assisted facile reduction of highly stable oleic acid coated CoFe2O4 to metallic Fe under vacuum annealing Universal behavior of surfactant assisted facile reduction of MFe2O4 (M = Mn, Fe, Co and Zn) nanoparticles during vacuum annealing Role of size in the reduction of surfactant coated Fe3O4 nanoparticles during in situ vacuum annealing is studied systematically It has been demonstrated that the particle size and magnetic properties of CoFe2O4 nanoparticles can be tuned by controlling the solvent polarity of the reaction medium during co-precipitation. New insights into the role of Oswald ripening on the growth mechanism in CoFe2O4 were obtained. The effect of Co 2+ and Fe 3+ metal ion concentration on particle size and magnetic properties shows that a small amount of paramagnetic ferrihydrite is formed when the Co 2+ ion concentration exceeds 0.1 M. 5

6 LIST OF REFERENCES 1. Dr. John Philip (Thesis superviser) Scientific Officer G Head, SMART Section, Non Destructive Evaluation Division, Indira Gandhi Centre for Atomic Research, Kalpakkam , India. 2. Dr. C. Venkateswaran Assistant Professor, Department of Nuclear Physics, University of Madras (Guindy Campus), Chennai , India. 3. Dr. S.V.M. Satyanarayana, Assistant Professor, Department of Physics, Pondicherry University, Pondicherry , India 4. Dr. T. Jayakumar Outstanding Scientist, Director, Metallurgy and Materials Group and Head, Non Destructive Evaluation Division, Indira Gandhi Centre for Atomic Research, Kalpakkam , India. 5. Prof. M.S. Hegde, Convener, Talent development centre, Indian Institute of Science (kudapura campus), Chitradurga District, Karnataka , India. philip@igcar.gov.in Ph. No.: , Ext (Direct) Fax. : cvenkateswaran@hotmail.com Ph. No.: (Direct), (Office) FAX : svmsatya@gmail.com satya.phy@pondiuni.edu.in Ph. No.: (Direct) Mobile: tjk@igcar.gov.in Ph. No.: / (O), /22805 (Direct) FAX: / mshegde@sscu.iisc.ernet.in Tel: +91(0)