Abstract
The internal morphology and magnetic properties of layer-by-layer assembled nanofilms of polyaniline (PANI) and maghemite (γ-Fe2O3—7.5-nm diameter) were probed with cross-sectional transmission electron microscopy (TEM) and magnetization measurements (magnetic hysteresis loops, magnetization using zero-field cooled/field-cooled protocols, and ac magnetic susceptibility). Additionally, simulations of the as-produced samples were performed to assess both the nanofilm’s morphology and the corresponding magnetic signatures using the cell dynamic system (CDS) approach and Monte Carlo (MC) through the standard Metropolis algorithm, respectively. Fine control of the film thickness and average maghemite particle–particle within this magnetic structure was accomplished by varying the number of bilayers (PANI/γ-Fe2O3) deposited onto silicon substrates or through changing the concentration of the maghemite particles suspended within the colloidal dispersion sample used for film fabrication. PANI/γ-Fe2O3 nanofilms comprising 5, 10, 25 and 50 deposited bilayers displayed, respectively, blocking temperatures (T B) of 30, 35, 39 and 40 K and effective energy barriers (ΔE/k B) of 1.0 × 103, 2.3 × 103, 2.8 × 103 and 2.9 × 103 K. Simulation of magnetic nanofilms using the CDS model provided the internal morphology to carry on MC simulation of the magnetic properties of the system taking into account the particle–particle dipolar interaction. The simulated (using CDS) surface–surface particle distance of 0.5, 2.5 and 4.5 nm was obtained for nanofilms with thicknesses of 36.0, 33.9 and 27.1 nm, respectively. The simulated (using MC) T B values were 33.0, 30.2 and 29.5 K for nanofilms with thicknesses of 36.0, 33.9 and 27.1 nm, respectively. We found the experimental (TEM and magnetic measurements) and the simulated data (CDS and MC) in very good agreement, falling within the same range and displaying the same systematic trend. Our findings open up new perspectives for fabrication of magnetic nanofilms with pre-established (simulated) morphology and magnetic properties.
Similar content being viewed by others
References
Alcantara GB, Paterno LG, Fonseca FJ, Morais PC, Soler MAG (2011) Morphology of cobalt ferrite nanoparticle-polyelectrolyte multilayered nanocomposites. J Magn Magn Mater 323:1372–1377
Alessio P, Rodríguez-Méndez ML, De Saja Saez JA, Constantino CJL (2010) Iron phthalocyanine in non-aqueous medium forming layer-by-layer films: growth mechanism, molecular architecture and applications. Phys Chem Chem Phys 12:3972–3983
Bahiana M, Oono Y (1990) Cell dynamical system approach to block copolymers. Phys Rev A 41:6763–6771
Balazs AC, Emrick T, Russell TP (2006) Nanoparticle polymer composites: where two small worlds meet. Science 314:1107–1110
Baldi G, Bonacchi D, Innocenti C, Lorenzi G, Sangregorio C (2007) Cobalt ferrite nanoparticles: The control of the particle size and surface state and their effects on magnetic properties. J Magn Magn Mater 311:10–16
Bastos CSM, Bahiana M, Nunes WC, Novak MA, Altbir D, Vargas P, Knobel M (2002) Role of the alloy structure in the magnetic behavior of granular systems. Phys Rev B 66:214407
Blums E, Cebers A, Maiorov MM (1985) Magnetic Fluids. Walter de Gruyter, Berlin
Correa-Duarte MA, Giersig M, Kotov NA, Liz-Marzan LM (1998) Control of packing order of self-assembled monolayers of magnetite nanoparticles with and without SiO2 coating by microwave irradiation. Langmuir 14:6430–6435
Decher G (1997) Fuzzy nanoassemblies: toward layered polymeric multicomposites. Science 277:1232–1237
Dey S, Mohanta K, Pal AJ (2010) Magnetic-field-assisted layer-by-layer electrostatic assembly of ferromagnetic nanoparticles. Langmuir 26:9627–9631
Dormann JL, Fiorani D, Tronc E (1997) Magnetic relaxation in fine-particle systems. In Prigogine I, Rice SA (eds) Adv Chem Phys 98: 283–494
Dutta P, Manivannan A, Seehra MS, Shah N, Huffman GP (2004) Magnetic properties of nearly defect-free maghemite nanocrystals. Phys Rev B 70:174428
Gittleman JI, Abeles B, Bozowski S (1974) Superparamagnetism and relaxation effects in granular Ni-SiO2 and Ni-Al2O3 films. Phys Rev B 9:3891–3897
Grigoriev D, Gorin D, Sukhorukov GB, Yashchenok A, Maltseva E, Mohwald H (2007) Polyelectrolyte/magnetite nanoparticle multilayers: preparation and structure characterization. Langmuir 23:12388–12396
Hendriksen PV, Bodker F, Linderoth S, Wells S, Morup S (1994) Ultrafine maghemite particles: I. Studies of induced magnetic textures. J Phys: Condens Matter 6:3081–3090
Janáky C, Visy C (2008) Synthesis and characterization of poly(3-octylthiophene)/γ-Fe2O3 nanocomposite – a promising combination of superparamagnetic-thermoelectric-conducting properties. Synth Met 158:1009–1014
Kim HS, Sohn BH, Lee W, Lee J-K, Choi SJ, Kwon SJ (2002) Multifunctional layer-by-layer self-assembly of conducting polymers and magnetic nanoparticles. Thin Solid Films 419:173–177
Kodama RH (1999) Magnetic nanoparticles. J Magn Magn Mater 200:359–372
Liu T-Y, Hu S-H, Liu D-M, Chen S-Y, Chen I-W (2009) Biomedical nanoparticle carriers with combined thermal and magnetic responses. Nano Today 4:52–65
MacDiarmid AG (2001) Synthetic metals: a novel role for organic polymers. Synth Met 125:11–22
Mamedov AA, Ostrander J, Aliev F, Kotov NA (2000) Stratified assemblies of magnetite nanoparticles and montmorillonite prepared by the layer-by-layer assembly. Langmuir 16:3941–3949
Mattoso LHC, Manohar SK, MacDiarmid AG, Epstein AJ (1995) Studies on the chemical syntheses and on the characteristics of polyaniline derivatives. J. Polym Sci Part A 33:1227–1234
Novak MA, Folly WSD, Sinnecker JP, Soriano S (2005) Relaxation in magnetic nanostructures. J Mag Magn Mat 294:133–140
Nowak U, Chantrell RW, Kennedy EC (2000) Monte Carlo simulation with time step quantification in terms of Langevin dynamics. Phys Rev Lett 84:163–166
Ohlan A, Singh K, Chandra A, Dhawan SK (2008) Microwave absorption properties of conducting polymer composite with barium ferrite nanoparticles in 12.4–18 GHz. Appl Phys Lett 93:053114
Oono Y, Bahiana M (1988) 2/3 -Power Law for copolymer lamellar thickness implies a 1/3 –Power law for spinodal decomposition. Phys Rev Lett. 61:1109–1111
Oono Y, Puri S (1987) Computationally efficient modeling of ordering of quenched phases. Phys Rev Lett 58:836–839
Oono Y, Puri S (1988) Study of phase-separation dynamics by use of cell dynamical systems I. Modeling. Phys Rev A 38:434–453
Oono Y, Shiwa Y (1987) Computationally efficient modeling of block copolymer and Bernard pattern formations. Modern Phys Lett B 1:49–55
Oono Y, Yeung C (1987) A cell dynamical system model of chemical turbulence. J Stat Phys 48:593–644
Paterno LG, Fonseca FJ, Alcantara GB, Soler MAG, Morais PC, Sinnecker JP, Novak MA, Lima ECD, Leite FL, Mattoso LHC (2009a) Fabrication and characterization of nanostructured conducting polymer films containing magnetic nanoparticles. Thin Solid Films 517:1753–1758
Paterno LG, Soler MAG, Fonseca FJ, Sinnecker JP, Sinnecker EHCP, Lima ECD, Novak MA, Morais PC (2009b) Layer-by-layer assembly of bifunctional nanofilms: surface-functionalized maghemite hosted in polyaniline. J Phys Chem C 113:5087–5095
Paterno LG, Soler MAG, Fonseca FJ, Sinnecker JP, Sinnecker EHCP, Lima ECD, Báo SN, Novak MA, Morais PC (2010) Magnetic nanocomposites fabricated via the layer-by-layer approach. J Nanosci Nanotechnol 10:2679–2685
Pedroza RC, da Silva SW, Soler MAG, Sartoratto PPC, Rezende DR, Morais PC (2005) Raman study of nanoparticle-template interaction in a CoFe2O4/SiO2-based nanocomposite prepared by sol–gel method. J Magn Magn Mater 289:139–141
Pereira Nunes JP, Bahiana M, Bastos CSM (2004) Magnetization curves as probes of Monte Carlo simulation of nonequilibrium states. Phys Rev E 69:56703
Pereira A, Alves S, Casanova M, Zucolotto V, Bechtold IH (2010) The use of colloidal ferrofluid as buiding blocks for nanostructured layer-by-layer films fabrication. J Nanopart Res 12:2779–2785
Polyak B, Fishbein I, Chorny M, Alferiev I, Williams D, Yellen B, Friedman G, Levy RJ (2008) High field gradient targeting of magnetic nanoparticle-loaded endothelial cells to the surfaces of steel stents. PNAS 105:698–703
Popplewell J, Sakhnini L (1995) The dependence of the physical and magnetic properties of magnetic fluids on particle size. J Magn Magn Mater 149:72–78
Qu TL, Zhao YG, Tian HF, Xiong CM, Guo SM, Li JQ (2007) Rectifying property and giant positive magnetoresistance of Fe3O4/SiO2/Si heterojunction. Appl Phys Lett. 90:223514
Ross CA (2001) Patterned magnetic recording media. Annu Rev Mater Sci 31:203–235
Royer F, Jamon D, Rousseau JJ, Roux H, Zins D, Cabuil V (2005) Magneto-optical nanoparticle-doped silica-titania planar waveguides. Appl Phys Lett. 86:01107
Sharma R, Chen CJ (2009) Newer nanoparticles in hyperthermia treatment and thermometry. J Nanopart Res 11:671–689
Shendruk TN, Desautels RD, Southern BW, van Lierop J (2007) The effect of surface spin disorder on the magnetism of γ-Fe2O3 nanoparticle dispersions. Nanotechnology 18:455704
Soler MAG, Lima ECD, Nunes ES, Silva FLR, Oliveira AC, Azevedo RB, Morais PC (2011) Spectroscopic study of maghemite nanoparticles surface-grafted with DMSA. J Phys Chem A 115:1003–1008
Suda M, Miyazaki Y, Hagiwara Y, Sato O, Shiratori S, Einaga Y (2005) Photoswitchable magnetic layer-by-layer films consisting of azobenzene derivatives and iron oxide nanoparticles. Chem Lett. 34:1028–1029
Wang X, Tang S, Liu J, He Z, An L, Zhang C, Hao J, Feng W (2009) Uniform Fe3O4-PANi/PS composite spheres with conductive and magnetic properties and their hollow spheres. J Nanopart Res 11:923–929
Acknowledgments
Maria A. G. Soler thanks Professor Steve Granick (Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, USA) for the hospitality in the period April–June, 2009, and CAPES-Brazil (4410-08-4). We are grateful to Dr. Wacek Swiech, Dr. Michael Marshall and Dr. Changhui Lei (Frederick Seitz Materials Research Laboratory, USA) for the support in the cross-sectional TEM measurements, Dr. Emilia C. D. Lima (Universidade Federal de Goiás, Brazil) for supplying the magnetic fluid samples and the Brazilian agencies CAPES, FAPERJ and MCT-CNPq for supporting this work.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Soler, M.A.G., Paterno, L.G., Sinnecker, J.P. et al. Assembly of γ-Fe2O3/polyaniline nanofilms with tuned dipolar interaction. J Nanopart Res 14, 653 (2012). https://doi.org/10.1007/s11051-011-0653-z
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s11051-011-0653-z