Study of molecular surface coating on the stability of maghemite nanoparticles

• Published in: Surface science Vol. 601; no. 18; pp. 3921 - 3925
• Main Authors: Soler, M.A.G., Alcantara, G.B., Soares, F.Q., Viali, W.R., Sartoratto, P.P.C., Fernandez, J.R.L., da Silva, S.W., Garg, V.K., Oliveira, A.C., Morais, P.C.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Lausanne Elsevier B.V 15-09-2007; Amsterdam Elsevier Science; New York, NY
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Grafting coefficient; Maghemite nanoparticle; Magnetic fluid; Physics; Raman spectroscopy; Surface passivation; Magnetic fluid; Raman spectroscopy; Surface passivation; Maghemite nanoparticle; Grafting coefficient; Nanoparticles; Raman spectra; Surface coating; Magnetic fluids; Passivation
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/j.susc.2007.04.029

In this study γ-Fe
2O
3 nanoparticle, surface-coated with increasing amount of oleic acid, have been prepared while the stability against particle degradation under laser excitation intensity was investigated. Maghemite nanoparticle was obtained via oxidation of magnetite nanoparticle, the latter synthesized by co-precipitation of Fe (II) and Fe (III) ions in alkaline medium. By varying the experimental conditions of surface-coating maghemite nanoparticles with oleic acid, samples with different grafting coefficient were obtained and investigated using X-ray diffraction and different spectroscopic techniques, namely Raman, Mössbauer, and infrared. The amount of oleic acid adsorbed on the maghemite surface was estimated via the carbon content obtained from elemental analysis.