The huge versatility of metal oxide nanoparticles: from catalytic to biomedical applications

This thesis work focused on the synthesis, characterization and application of magnetic nanoparticles based on iron oxides. At the beginning, the synthesis of maghemite nanoparticles was optimized and an inert coating was studied . This coating could allow the magnetic core to be covered without obscuring the magnetic properties too much, in order to use the system as a recyclable support for organometallic complexes. The chosen coating was silica and we proceeded by anchoring organometallic complexes of Molybdenum and Vanadium in order to study their reactivity and recyclability, both in organic and aqueous solvents. Subsequently, it was decided to synthesize mixed oxides by adding Nickel and Cobalt to the iron oxides, in order to obtain systems with different magnetic properties. This study led to the obtaining of heterogeneous catalysts in which the different magnetic cores were used as supports for catalytically active Palladium and Ruthenium nanoparticles. In this case it was decided to test the systems for unconventional catalysis, which involved the use of an alternating magnetic field to provide energy to the reaction, instead of using heating through the thermal pathway. For this work, the magnetic properties of the cores were not only used for the recovery of the catalyst, but also for the heating of the reaction itself. Finally, the biomedical application of magnetic nanoparticles was also explored, using it as a basis for the synthesis of metal phenolic networks also containing Gadolinium, used in imaging. Particular attention in all the works was placed on the in-depth characterization of the systems, using techniques such as: ATR-IR, XRD, XPS, SEM, TEM, AGFM. The data collected by all these techniques allowed us to have a more than complete picture of the synthesized systems.