Convective Self Assembly of Fe3O4Nanoparticles on Si
Substrate
T Thanveer1, M. R. Varma1 and S Thomas1#
Materials Science and Technology Division, CSIR- NIIST Thiruvananthapuram-695019, India
#email: senoythomas@gmail.com
Interest over magnetic nanoparticles is due to the fact that they exhibit peculiar characteristics compared to their
bulk existence [1]. Large surface to volume ratio, and superparamagnetic behavior of magnetic nanoparticles offer a
huge potential in different areas of applications such as magnetic hyperthermia[2], ferrofluids[3] and biomedicine[4].
They are also model systems for studying fundamental aspects such as finite size effects and inter-particle magnetic
interactions. In this respect, large arrays of magnetic nanoparticles are preferred over individual particles.
Here, we report fabrication of arrays of Fe3O4 nanoparticles on thermally oxidized Si substrates. Initially, Fe3O4
nanoparticles were synthesized by co-precipitation of Fe(II) and Fe(III) ions in ammonium hydroxide at ambient
conditions. Oleic acid was used as a surfactant. The adopted technique is a simplified way to synthesize Fe3O4
nanoparticles and opens up room for control over particle size. To self assemble nanoparticles on thermally oxidised
Si substrates, convective self assembly procedure is followed [5]. Though the method is simple, dispersed
nanoparticles can effectively be assembled on the substrate. The nanoparticles were deposited by dragging the
meniscus of microlitre suspension droplets trapped between two plates[6]. This technique offers reduced material
consumption compared to standard dip coating process.
The crystalline structure of nanoparticles were investigated with x-ray difractometer. The surface functionalisation
of the nanoparticles were characterized by FTIR spectroscopy. Transmission electron microscopy and atomic force
microscopy was employed to obtain information about the morphology and size of the nanoparticles. The obtained
results are summarized in this presentation.
Acknowledgement
This work is financially supported by the Department of Science and Technology, Government of India through
INSPIRE Faculty programme
References:
[1] Taeghwan Hyeon “Chemical synthesis of magnetic nanoparticles” Chem. Commun., 8 (2003) 927–934
[2]Gerardo F. Goya, Enio Lima, Jr., Amanda D. Arelaro, Teobaldo Torres, Hercilio R. Rechenberg, Liane Rossi,
Clara Marquina, and M. Ricardo Ibarra“Magnetic Hyperthermia with Fe3O4 nanoparticles: the Influence of
Particle Size on Energy Absorption” IEEE.Trans.Magn. 44,( 2008) 4444-4447
[3] R. Hiergeist, W. Andrä, N. Buske, R. Hergt, I. Hilger, U. Richter, andW. Kaiser, “Application of magnetite
ferrofluids for hyperthermia,” J. Magn. Magn. Mater., 201, (1999) 420–422.
[4] P. Tartaj, M. del Puerto Morales, S. Veintemillas-Verdaguer, T.González-Carreño, and C. J. Serna, “The
preparation of magneticnanoparticles for applications in biomedicine,” J. Phys. D: Appl. Phys., 36 (2003) 182–197
[5] Brian G. Prevo and Orlin D. Velev “Controlled, Rapid Deposition of Structured Coatings from Micro and
Nanoparticle Suspensions” Langmuir 20 (2004) 2099-2107
[6] Brian G. Prevo1, Daniel M. Kuncicky, Orlin D. Velev “Engineered deposition of coatings from nano and
microparticles:A brief review of convective assembly at high volume fraction” Colloids and Surfaces A:
Physicochem. Eng. Aspects 311 (2007) 2–10