Abstract. Co nanoclusters were synthesized by an inverse-micelle chemical route. Themagnetic and microstructural properties of the nanoparticles have been analyzed as a functionof the surfactant (AOT and DEHP) and the drying method. Microstructural analysis has beenperformed by TEM and XANES; magnetic properties have been studied by hysteresis loopsand zero-field cooling - field cooling (ZFC-FC) curves. TEM images show 2 to 4 nm sizedparticles spherical in shape. XANES measurements point out a significant presence of Co3O4with metallic Co and some Co2+ bound to the surfactant. The presence of antiferromagneticCo3O4 explains the magnetic transition observed at low T in both ZFC-FC measurements andhysteresis loops. Finally, the presence of magnetic interactions explains the bigger effectivecluster size obtained from hysteresis loops fits (6-10 nm) compared to the sizes observed byTEM (2-4 nm).
|Numero di pagine||4|
|Rivista||JOURNAL OF PHYSICS. CONFERENCE SERIES|
|Stato di pubblicazione||Published - 2010|
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
Ruggirello, A. M., Turco Liveri, V., Torchio, Alonso, Capellini, Neisius, García Prieto, Fdez-Gubieda, Mobilio, Longo, A., & Meneghini (2010). Magnetic properties of colloidal cobalt nanoclusters. JOURNAL OF PHYSICS. CONFERENCE SERIES, 200, 072100-072103.