Synthesis of magnetic microporous organic nanotube networks for adsorption application

In this work, we report a novel synthesis of magnetic microporous organic nanotube networks (Fe₃O₄-MONNs) by an in situ hyper-cross-linking reaction between magnetic nanoparticles and core-shell bottlebrush copolymers. The resulting Fe₃O₄-MONNs magnetic hybrid materials display a hierarchically porous structure with nanotube morphology, large surface area (648 m² g^-1) and uniform mesochannels (∼4 nm). Due to abundant anionic carboxylate groups produced as end-groups after polylactide (PLA) core degradation in the bottlebrush copolymers, the Fe₃O₄-MONNs showed a selective adsorption behavior for the cationic dyes. Moreover, the Fe₃O₄-MONNs possess superparamagnetism and high saturation magnetization (19.8 emu g^-1), which allows them to be easily separated by an external magnetic field and subsequently reused. Therefore, this work provides a promising method for the design and synthesis of magnetic microporous organic nanotube networks, which can be used for the practical separation of organic dyes, as well as having other potential applications in the fields of absorption, fast separation and heterogeneous catalysis.