TY - JOUR
T1 - Magnetic properties of colloidal cobalt nanoclusters
AU - Ruggirello, Angela Monia
AU - Turco Liveri, Vincenzo
AU - Torchio, null
AU - Alonso, null
AU - Capellini, null
AU - Neisius, null
AU - García Prieto, null
AU - Fdez-Gubieda, null
AU - Mobilio, null
AU - Longo, Alessandro
AU - Meneghini, null
PY - 2010
Y1 - 2010
N2 - 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).
AB - 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).
KW - cobalt nanoparticles
KW - cobalt nanoparticles
UR - http://hdl.handle.net/10447/50909
M3 - Article
VL - 200
SP - 72100
EP - 72103
JO - JOURNAL OF PHYSICS. CONFERENCE SERIES
JF - JOURNAL OF PHYSICS. CONFERENCE SERIES
SN - 1742-6588
ER -