Magnetic polymer bowl for enhanced catalytic activity and recyclability

This work introduces the fabrication of a magnetic polymer bowl for enhanced catalytic activity and recyclability, which involves the synthesis of silica-coated Fe₃O₄magnetic clusters, seeded dispersion polymerization using the magnetic clusters, and transformation into a bowl-like structureviaa phase separation route. The additional treatment with tannic acid (TA) on the bowls allows thein situformation of silver nanoparticles (AgNPs) on their surfaces. The openness and larger surface area of the bowls, as compared with those of other structured particles, such as spheres and flowers, enable a considerably higher immobilization of AgNPs, thus leading to an excellent catalytic reduction for 4-nitrophenol (4-NP), methylene blue (MB), and rhodamine B. Furthermore, the strong magnetic response originating from the magnetic clusters inside the bowls endows a good magnetic recovery and an excellent reusability for the repeated reduction of the organic dyes without loss of catalytic activity.