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Pàgina inicial > Articles > Articles publicats > Seeded Growth Synthesis of Au-Fe3O4 Heterostructured Nanocrystals : |
Data: | 2017 |
Resum: | Multifunctional hybrid nanoparticles comprising two or more entities with different functional properties are gaining ample significance in industry and research. Due to its combination of properties, a particularly appealing example is Au-FeO composite nanoparticles. Here we present an in-depth study of the synthesis of Au-FeO heterostructured nanocrystals (HNCs) by thermal decomposition of iron precursors in the presence of preformed 10 nm Au seeds. The role of diverse reaction parameters on the HNCs formation was investigated using two different precursors: iron pentacarbonyl (Fe(CO)) and iron acetylacetonate (Fe(acac)). The reaction conditions promoting the heterogeneous nucleation of FeO onto Au seeds were found to significantly differ depending on the precursor chosen, where Fe(acac) is considerably more sensitive to the variation of the parameters than Fe(CO) and more subject to homogeneous nucleation processes with the consequent formation of isolated iron oxide nanocrystals (NCs). The role of the surfactants was also crucial in the formation of well-defined and monodisperse HNCs by regulating the access to the Au surface. Similarly, the variations of the [Fe]/[Au] ratio, temperature, and employed solvent were found to act on the mean size and the morphology of the obtained products. Importantly, while the optical properties are rather sensitive to the final morphology, the magnetic ones are rather similar for the different types of obtained HNCs. The surface functionalization of dimer-like HNCs with silica allows their dispersion in aqueous media, opening the path to their use in biomedical applications. |
Ajuts: | Agència de Gestió d'Ajuts Universitaris i de Recerca 2014/SGR-1015 Agència de Gestió d'Ajuts Universitaris i de Recerca 2014/SGR-612 Agència de Gestió d'Ajuts Universitaris i de Recerca 2014/SGR-672 Ministerio de Economía y Competitividad MAT2013-48628-R Ministerio de Economía y Competitividad MAT2013-41506 Ministerio de Economía y Competitividad MAT2015-70725-R Ministerio de Economía y Competitividad MAT2016-79455-P Ministerio de Economía y Competitividad MAT2016-77391-R European Commission 685817 Ministerio de Economía y Competitividad RYC-2012-10991 European Commission 322153 Ministerio de Economía y Competitividad SEV-2013-0295 |
Drets: | Tots els drets reservats. |
Llengua: | Anglès |
Document: | Article ; recerca ; Versió sotmesa a revisió |
Matèria: | Biomedical applications ; Composite nanoparticles ; Dispersion in aqueous media ; Functional properties ; Heterogeneous nucleation ; Homogeneous nucleation ; Iron oxide nanocrystals ; Surface Functionalization |
Publicat a: | Chemistry of materials, Vol. 29, Issue 9 (May 2017) , p. 4022-4035, ISSN 1520-5002 |
Preprint 37 p, 2.3 MB |