Fe(3)O(4)@Resorcinol–Formaldehyde Resin/Cu(2)O Composite Microstructures: Solution-Phase Construction, Magnetic Performance, and Applications in Antibacterial and Catalytic Fields

[Image: see text] Multifunctional Fe(3)O(4)@resorcinol–formaldehyde resin/Cu(2)O composite microstructures (denoted as Fe(3)O(4)@RF/Cu(2)O microstructures) were successfully constructed via a simple wet chemical route that has not been reported so far in the literature. The as-obtained Fe(3)O(4)@RF/Cu(2)O microstructures were characterized using field-emission scanning electron microscopy, (high-resolution) transmission electron microscopy, selected-area electron diffraction, X-ray diffraction, and X-ray energy dispersive spectroscopy. The investigations showed that the as-obtained microstructures presented not only excellent antibacterial activity to Staphylococcus aureus (Gram-positive bacteria) and Escherichia coli (Gram-negative bacteria) but also highly efficient catalytic ability for the reduction of 4-nitrophenol (4-NP) in a solution with excess NaBH(4). Owing to the presence of Fe(3)O(4), the antibacterial reagent and the catalyst could be readily collected from the mixed systems under the assistance of an external magnetic field. It was found that the as-obtained microstructures displayed good cycling stability in antibacterial and catalytic applications. Fe(3)O(4)@RF/Cu(2)O microstructures still retained more than 87% of the antibacterial efficiency after 5 cycles and 89% of the catalytic efficiency after 10 cycles.