Catalytic oxidation of alcohols catalyzed by gold-coated iron oxide magnetic nanoparticles in water

Gold-coated magnetic iron oxide nanoparticles (ION) (Fe3O4@Au) were synthesized and utilized as catalyst for alcohol oxidation with tert-butyl hydroperoxide (TBHP). First, iron oxide magnetic nanoparticles (Fe3O4) were prepared and finally coated with a thin layer of gold. Structure and composition of Fe3O4@Au nanocatalyst were characterized by XRD, TGA, and FT-IR analysis. Size and morphology and size of particles were determined through TEM. Surface properties and topographies of coated nanoparticles were investigated by the AFM technique. The magnetic properties of Fe3O4 and Fe3O4@Au nanoparticles were measured by VSM technique. After confirming the structure of gold-coated magnetic ION, its performance for the oxidation of various aliphatic and aromatic alcohols with TBHP was studied in water. Finally, the reusability of Fe3O4@Au nanocatalyst was evaluated after five consecutive cycles in the 4-methoxybenzyl alcohol oxidation. The measured results revealed that the gold-coated iron oxide magnetic nanoparticles can be reused well in the oxidation processes of alcohols with high efficiency.