Characterization of Surface Morphology and Magnetic Properties of Fe3O4-Deposited Alginate Bead

Abstract

It is generally known that Fe₃O₄ nanoparticles are magnetically separable and thus, have been widely used in water treatment. However, magnetophoresis of the singly dispersed Fe₃O₄ nanoparticles has been proven to be slow. Realizing this limitation, the present work aims to immobilise various quantities of nano-Fe₃O₄ onto the surface of an alginate bead to promote cooperative magnetophoresis. The formed nano-Fe₃O₄ deposited alginate beads were characterized for their surface morphology and magnetic properties using scanning electron microscopy (SEM) and vibrating sample magnetometry (VSM), respectively. SEM analysis showed that the external surface of the alginate bead turns porous upon subjecting to sonication process. The pores serve as the template to hold the Fe₃O₄ nanoparticles in place. Upon the deposition of Fe₃O₄ nanoparticles, the external surface of alginate bead turned rougher. Besides changes in surface morphology, the saturation magnetization value of the beads recorded a substantial increment along with the loading amount of Fe₃O₄. Such observation proved that it is feasible to induce a cooperative magnetic effect by immobilise various quantities of Fe₃O₄ onto the surface of alginate bead.