Fe3O4@graphene oxide composite: A magnetically separable and efficient catalyst for the reduction of nitroarenes

Abstract We reported a facile co-precipitation method to prepare a highly active Fe 3 O 4 @graphene oxide (Fe 3 O 4 @GO) composite catalyst, which was fully characterized by means of X-ray diffraction (XRD), Fourier transformed infrared (FTIR) spectroscopy, transmission electron microscopy (TEM) and N 2 adsorption–desorption measurements. The results demonstrated that the Fe 3 O 4 nanoparticles (Fe 3 O 4 NPs) with a small diameter of around 12 nm were densely and evenly deposited on the graphene oxide (GO) sheets. The as-prepared Fe 3 O 4 @GO composite was explored as a catalyst to reduce a series of nitroarenes for the first time, which exhibited a great activity with a turnover frequency (TOF) of 3.63 min −1 , forty five times that of the commercial Fe 3 O 4 NPs. The dosages of catalyst and hydrazine hydrate are both less than those reported. Furthermore, the composite catalyst can be easily recovered due to its magnetic separability and high stability.