A MECHANISM FOR THE ADSORPTION OF CARBOXYLIC ACIDS ONTO THE SURFACE OF MAGNETIC NANOPARTICLES

• Published in: Materiali in tehnologije Vol. 42; no. 2; pp. 79 - 83
• Main Authors: Drmota, Ana, Kosak, Aljosa, Znidarsic, Andrej
• Format: Journal Article
• Language: Slovenian
• Published: 01.03.2008
• ISSN: 1580-2949; 1580-3414

The unique properties of magnetic nanoparticles, which are dominated by superparamagnetism, and the size dependence of those properties have led to a number of technological and biomedical applications of these materials and to the preparation of stable magnetic fluids or ferrofluids. The main problem relating to the stability of ferrofluids is the difficulty in controlling the dispersion of magnetic nanoparticles inside a liquid medium. To overcome this problem, functionalization of the nanoparticle surface is required. The efficiency of the functionalization process depends on the adsorption mechanism, which involves interactions of the surface-active agent molecules with the nanoparticle surface. The adsorption mechanism for oleic acid onto the surface of maghemite (y-Fe2O3) nanoparticles prepared with the classic coprecipitation method was followed in solution using in-situ infrared spectroscopy (ReactIR). The synthesized maghemite nanoparticles were characterized using transmission electron microscopy (TEM), X-ray diffractometry (XRD) and specific surface area measurements (BET). The specific magnetization of the prepared samples was measured at room temperature with a DSM-10 magneto-susceptometer.