Functionalized magnetite particles for adsorption of colloidal noble metal nanoparticles

Joana L Lopes; Karine L Marques; Ana V Girão; Eduarda Pereira; Tito Trindade

doi:10.1016/j.jcis.2016.04.046

Functionalized magnetite particles for adsorption of colloidal noble metal nanoparticles

J Colloid Interface Sci. 2016 Aug 1:475:96-103. doi: 10.1016/j.jcis.2016.04.046. Epub 2016 Apr 28.

Authors

Joana L Lopes¹, Karine L Marques¹, Ana V Girão¹, Eduarda Pereira¹, Tito Trindade²

Affiliations

¹ Department of Chemistry, CICECO, Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal.
² Department of Chemistry, CICECO, Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal. Electronic address: tito@ua.pt.

PMID: 27156089
DOI: 10.1016/j.jcis.2016.04.046

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.

Keywords: Magnetic separation; Magnetite; Nanometals; Nanoparticles.