Rhodium Nanoparticles Loaded on Carbon-Wrapped Fe3O4 Sphere: an Efficient, Stable and Magnetically Recoverable Catalyst for the Catalytic Transfer Hydrogenation of Nitroarenes in Water

The carbon wrapped magnetic nanosphere Fe3O4@C (similar to 300 nm) was prepared under simple hydrothermal conditions, and it served as the carrier of Rh nanoparticles (2-3 nm), which acted as the highly efficient catalyst for reduction of nitro compounds, and reutilization of catalyst is convenient to achieve because the catalyst particles are magnetic. A scope of nitroarene derivatives were reduced to corresponding anilines in water, and the reactions completed in 10 min with nearly quantitative conversions and 100% selectivity. In addition, the abundant oxygen-containing functionality on the carbon shell which can strongly binds the Rh-NPs to offer extraordinary stability is investigated by using various techniques, including transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-Ray Diffraction (XRD), and Fourier transform infrared spectrometer (FT-IR).