Biosynthesis of multiphase iron nanoparticles using Syzygium aromaticum and their magnetic properties

Its desirable to design nanomaterials with diminution of environmental hazards and with specific functional characteristics including magnetic properties. However, the utilization of plant extracts for nanoparticles synthesis are advantageous as they are ecofriendly and sustainable. Polyphenols from certain plant extract can also form iron complexes and thereby reducing them to metal nanoparticles and stabilising them. Herein, we report the green synthesis and characterization of multiphase magnetic iron nanoparticles using aqueous extracts of Syzygium aromaticum (CE-Fe NPs) with magnetic properties. The resultant material was characterised using various techniques. The compound crystallized into multiple phases of Iron oxide is evident from the XRD pattern. Iron oxide nanoparticles found to be of very small size from the electron microscopy images and the reduction can be attributed to the presence of polyphenols and organic acids from syzygium aromaticum extract. TGA analysis indicating good thermal stability and XPS analysis confirms the presence of mixed valance of Fe ions, i.e. both Fe3+ and Fe2+. Temperature variation of DC and AC magnetic studies reveals that the material exhibit a superparamagnetic-like nature with frustration of surface spins and thereby leading into a cluster glass-like behavior. Further, the phyto organic moieties from syzygium aromaticum associated with the surface of multiphase Fe nanoparticles the surface chemistry tuned by subsequent functionalization combined with their magnetic properties have great potential in wide range of applications including localised hyperthermia treatments.