Coating Fe3O4 spheres with polypyrrole-Pd composites and their application as recyclable catalysts

Abstract In this work, we reported one-step deposition of the 3-(mercaptopropyl)trimethoxysilane on magnetic Fe 3 O 4 spheres to form well-defined core-shell Fe 3 O 4 @SiO 2 -SH spheres. The thiol ( SH) groups could be converted easily to sulfonic acid ( SO 3 H) groups with H 2 O 2 and the as-obtained Fe 3 O 4 @SiO 2 -SO 3 H spheres were used as a platform for loading Pd 2+ ions. The Pd 2+ ions anchored on the Fe 3 O 4 @SiO 2 -SO 3 H spheres acted both as an oxidant for pyrrole monomer and as a source of palladium atoms, yielded polypyrrole(PPy)-Pd composites around the Fe 3 O 4 @SiO 2 -SO 3 H spheres. This strategy is very facile for fabricating magnetic conducting polymer-noble metal composites and the as-prepared Fe 3 O 4 @SiO 2 -SO 3 H@PPy-Pd composite spheres could act as efficient catalysts in reduction of 4-nitrophenol and Suzuki coupling reaction due to their high activity, ease of separation, and excellent reusability.