| Autor: |
Meftah S; CNRS, De la Molécule aux Nano-Objets: Réactivité, Interactions Spectroscopies, MONARIS, Sorbonne Université, 75005 Paris, France.; Roberval (Mechanics, Energy and Electricity), Centre de recherche Royallieu─CS, Université de technologie de Compiègne, 60 319-60 203 Compiègne Cedex, France., Ngo AT; CNRS, De la Molécule aux Nano-Objets: Réactivité, Interactions Spectroscopies, MONARIS, Sorbonne Université, 75005 Paris, France., Bouteiller L; CNRS, Institut Parisien de Chimie Moléculaire, IPCM, Sorbonne Université, 75005 Paris, France., Russier V; ICMPE UMR 7182 CNRS and Université UPE, 2-8 rue Henri Dunant, 94320 Thiais, France., Hrabovsky D; Plateforme Mesures Physiques à Basses Températures (MPBT), Sorbonne Université, 75005 Paris, France., Konaté A; Service d'Analyse Physico-Chimique, Université de Technologie de Compiègne, BP 20529, Compiègne Cedex F-60205, France., Kondo D; CNRS, Institut Jean Le Rond D'Alembert, Sorbonne Université, 75005 Paris, France., Bedoui F; Roberval (Mechanics, Energy and Electricity), Centre de recherche Royallieu─CS, Université de technologie de Compiègne, 60 319-60 203 Compiègne Cedex, France.; Materials and Process simulation Center, California institute of Technology, Pasadena 91106, California United States., Lisiecki I; CNRS, De la Molécule aux Nano-Objets: Réactivité, Interactions Spectroscopies, MONARIS, Sorbonne Université, 75005 Paris, France. |
| Abstrakt: |
We report the synthesis of uniform populations of spherical maghemite nanoparticles by thermal decomposition of iron precursors with tunable diameters centered at 3.3, 7.5, and 12.0 nm and tunable surface chemistry. The three stabilizing ligands were fatty acids with three different alkyl chain lengths (18, 12, and 8 carbon atoms). The unprecedented accurate control of the surface chemistry is made possible by the use of three types of iron complexes, that is, iron oleate (C18), iron dodecanoate (C12), and iron octanoate (C8), associated with fatty acid ligands having the same alkyl chain length, that is, oleic acid (C18), dodecanoic acid (C12), and octanoic acid (C8). Since the thermal decomposition of the iron precursor varies with the chain length, no general rules can be applied to control the nanoparticle size, but optimal synthesis conditions have been investigated to induce the growth of nanoparticles with three different surface chemistries, keeping the diameters centered at 3.3, 7.5, and 12.0 nm. Finally, structural characterization of the nine populations of maghemite nanoparticles was performed by transmission electron microscopy and X-ray diffraction, and magnetic properties were determined by using SQUID magnetometry. |
