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.