Hierarchical Fe₃O₄ microspheres supported chitosan/palladium nanocomposite as a recyclable catalyst

Designing reusable and stable catalysts with ease of synthesis is very important for chemical conversion reactions. Here, hierarchical Fe3O4 microspheres were prepared using facile surfactant free solvothermal method. Fe3O4 microspheres supported Chitosan/Pd nanocomposite was synthesized via cost-effective one-pot chemical reduction method. The nanocomposite was characterized using XRD, FTIR, SEM, EDX, FT-Raman and TGA analyses. XRD results confirm the presence of face-centered cubic-structured Fe3O4 and palladium in the nanocomposite. HRSEM images show monodispersed 3D hierarchical microspheres composed of nanospheres. The composite was found to have a superparamagnetic property due to the Fe3O4 microspheres and a combined magnetic saturation of 87.66 emu/g. The prepared material was tested for its catalytic performance toward reduction of 4-Nitrophenol(4-NP) to 4-Aminophenol(4-AP) and reaction followed the first-order kinetics with excellent catalytic performance. The incorporation of Fe3O4 microspheres in the composite significantly improved the stability and reusability.