Magnetic Gold Catalysts Obtained by Sequential Preparation for Highly Efficient Catalytic Reduction of Nitroaromatics

Noble metal catalysts have received considerable interests owing to their glamorous properties and applications in heterogeneous catalysis. In this work, the magnetic Au nanoparticles catalysts were successful fabricated via sequential preparation strategy at room temperature. 4-nitrophenol was chosen as the model molecule to evaluate the catalytic reduction activity for the preparation of amines from their corresponding nitroaromatics. The results showed that the catalytic reaction related with 4-nitrophenol could be achieved in 3 min, and the catalyst could be easily reused at least 15 cycles without significant reduction in activity when the as-prepared Fe3O4@CB6@Au0.4% nanoparticles acted as the catalyst. It revealed that the as-prepared catalyst exhibited outstanding catalytic performance and cycling stability. The SEM and TEM images demonstrated that the Au species presented in composite system in the form of highly dispersed Au0 nanoparticles, playing a crucial role in the catalytic process. Therefore, the Au nanoparticles combined with Fe3O4@CB6 prepared by the sequential preparation strategy had excellent catalytic reduction properties for nitroaromatics, and the method could open a new way for the design of other highly dispersed nanometallic materials.