(544fq) Catalytic Activity of Magnetic Nanoparticles Activated Via RF Induction Heating
To demonstrate this chemical transformation, ~20 nm iron oxide nanoparticle spheres, cubes, and truncated octahedrons of tunable sizes are investigated for RF induced catalysis. The size and shape of these particles is controlled by varying surfactant to precursor ratio in thermal decomposition reactions. These facets allow for the tuning of surface activity and heat generation, key parameters for selectivity and activity engineering. The heat generated is dependent on the spin configuration on the surface, with minimum heating rates at least 34% higher than commercially available particles. Surface functionalization with hydroxyl groups is performed to increase the interaction of Fe3O4 with alcohols in dehydrogenation reactions. Additionally, this localized heat generation can be used to control surface functionalization for dispersion in aqueous solutions and conversion of alcohols. For spherical particles, the GC-MS data shows production of aldehydes and esters via thermal routes while RF induced reactions result in longer alkenes such as decene. Additionally, the intensity of the magnetic field applied changes the reaction products. These results indicate changes in the reaction mechanism associated with RF activation. Furthermore, to investigate the role of the surface of iron oxide without any surfactants on the mechanism of the reaction, spherical nanoparticles are also synthesized via co-precipitation routes. The catalyst is characterized before and after functionalization and reaction steps to probe the crystal structure, oxidation states of iron and morphology of the particles, using XRD, XPS and HRTEM respectively. The reaction products are characterized via GC-MS to elucidate the reaction mechanism.