Fabrication of amino-functionalized Fe3O4@Cu3(BTC)2 for heterogeneous Knoevenagel condensation

Metal organic frameworks (MOFs) are an important platform for heterogeneous catalysts. Although MOFs with a smaller particle size exhibit better catalytic performance because of less diffusion limitations, their separation and recycling after catalytic reactions are difficult. The integration of MOFs with magnetic nanoparticles could facilitate their recovery and separation. Especially, the shell thickness of the core-shell structured composites is controllable. In this study, amino-functionalized Fe3O4@Cu3(BTC)2 was fabricated by a stepwise assembly method and its catalytic performance in Knoevenagel condensation was investigated. The results demonstrated that the magnetic hybrid material exhibited a core-shell structure, with a shell thickness of about 200 nm. Furthermore, it not only exhibited high catalytic activity, but remarkably, it could also be easily recovered magnetically and recycled without obvious loss of catalytic efficiency after three cycles.