title: Functionalized magnetite particles for adsorption of colloidal noble metal nanoparticles.
abstract: Magnetite (inverse spinel type) particles have been surface-modified with siliceous shells enriched in dithiocarbamate groups. The deposition of colloidal noble metal nanoparticles (Au, Ag, Pt, Pd) onto the modified magnetites can be performed by treating the respective hydrosols with the magnetic sorbents, thus allowing their uptake from water under a magnetic gradient. In particular, for Au colloids, these magnetic particles are very efficient sorbents that we ascribe to the strong affinity of sulfur-containing groups at the magnetite surfaces for this metal. Considering the extensive use of Au colloids in laboratorial and industrial contexts, the approach described here might have an impact on the development of nanotechnologies to recover this precious metal. En route to these findings, we varied several operational parameters in order to investigate this strategy as a new bottom-up assembly method for producing plasmonic-magnetic nanoassemblies.
authors.affiliation: Department of Chemistry, CICECO, Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Joana L
authors.initials: JL
authors.lastname: Lopes
authors.affiliation: Department of Chemistry, CICECO, Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Karine L
authors.initials: KL
authors.lastname: Marques
authors.affiliation: Department of Chemistry, CICECO, Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Ana V
authors.initials: AV
authors.lastname: Girão
authors.affiliation: Department of Chemistry, CICECO, Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Eduarda
authors.initials: E
authors.lastname: Pereira
authors.affiliation: Department of Chemistry, CICECO, Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal. Electronic address: tito@ua.pt.
authors.forename: Tito
authors.initials: T
authors.lastname: Trindade
keywords: Magnetic separation; Magnetite; Nanometals; Nanoparticles