Influence of the colloidal environment on the magnetic behavior of cobalt nanoparticles
The magnetic properties of 10 nm diameter surfactant-coated cobalt (Co) nanoparticles in 1,2-dichlorobenzene (DCB) are investigated by a series of sequential magnetic moment (m) vs temperature (T) measurements. A rapid rise in magnetic moment around 250 K during warming and an abrupt drop at 234 K d...
Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 23(2007), 23 vom: 06. Nov., Seite 11740-6 |
---|---|
1. Verfasser: | |
Weitere Verfasser: | , , |
Format: | Aufsatz |
Sprache: | English |
Veröffentlicht: |
2007
|
Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
Schlagworte: | Journal Article |
Zusammenfassung: | The magnetic properties of 10 nm diameter surfactant-coated cobalt (Co) nanoparticles in 1,2-dichlorobenzene (DCB) are investigated by a series of sequential magnetic moment (m) vs temperature (T) measurements. A rapid rise in magnetic moment around 250 K during warming and an abrupt drop at 234 K during cooling are observed when a nonsaturating external magnetic field is applied. Differential scanning calorimetry (DSC) measurements demonstrate that the rapid rise and abrupt drop in magnetization are associated with the melting and freezing of the solvent. Magnetic measurements of these Co nanoparticles in DCB are also used to probe their aging over a period of 70 days. The saturation magnetic moment of Co nanoparticles in DCB stored in air at room temperature decreases by nearly 40% over 70 days. Transmission electron microscopy (TEM) characterizations are reported to show the time evolution in the size, shape, and crystalline structures of DCB-immersed nanoparticles |
---|---|
Beschreibung: | Date Completed 15.01.2008 Date Revised 30.10.2007 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
ISSN: | 1520-5827 |