Synthesis, Characterization, and Nanocatalysis Application of Core-Shell Superparamagnetic Nanoparticles of Fe3O4@Pd

There is a wide number of different synthetic methods to obtain magnetite (Fe3O4) superparamagnetic nanoparticles (SPNPs). However, only a few are able to produce very small and well defined SPNPs with narrow size distribution. We report a modification of the metal-complex decomposition in organic media method in which we replace iron(III) acetylacetonate (Fe(Acac)(3)) with an iron-urea complex (Fe-Urea) as metal source for the synthesis. With this modification we were able to obtain small particle sizes with a good control in size distribution. The Fe-Urea complex is easy to prepare with excellent yields. Core-shell nanoparticles are then prepared using palladium(II) acetylacetonate as a Pd source, to obtain a Pd-0 shell stabilised by oleylamine. The core-shell superparamagnetic nanoparticles of Fe3O4@Pd-OA are extensively characterized by FT-IR, powder X-ray diffraction, transmission electron microscopy, UV-vis, thermogravi-metric analysis/differential scanning calorimetry, and magnetic susceptibility measurements, and tested in a palladiumcatalyzed cross-coupling Suzuki-Miyaura reaction with promising results.