In situ synthesis of silver supported nanoporous iron oxide microbox hybrids from metal–organic frameworks and their catalytic application in p-nitrophenol reduction

Abstract

Ag nanoparticles (NPs) are successfully grown in situ on nanoporous Fe₂O₃ microboxes (Ag/Fe₂O₃) simply by annealing Prussian blue (PB) in the presence of silver nitrate for the first time. The catalytic activity of the Ag/Fe₂O₃ microboxes for the reduction of p-nitrophenol (PNP) with NaBH₄ is measured by UV-vis spectroscopy. It is found that the composites exhibit bifunctional properties with high magnetization and excellent catalytic activity toward PNP reduction. The high catalytic activity of the catalyst might be attributed to its high surface area and the synergistic effect on the delivery of electrons between Ag NPs and Fe₂O₃ microboxes. In addition, efficient reduction is observed and found to depend upon the content of Ag in the Ag/Fe₂O₃ microboxes. The dosage of the catalyst and the reaction temperature were investigated. Furthermore, the catalysts can be easily recycled by applying an external magnetic field while maintaining the catalytic activity without significant decrease even after running six times. The unique properties provide an ideal platform to study various metal/Fe₂O₃ catalysts which can be potentially applied in a wide variety of fields of catalysis and green chemistry.