Magnetically Separable and Reusable Fe ₃ O ₄ Nanoparticles for Reduction of Nitroarenes in Water

Abstract Reduction of nitroarenes was achieved using magnetically separable and reusable iron oxide nanoparticles (Fe 3 O 4 @ RA NPs) using Rhododendron arboreum ( RA ) flower extract with high yields in water using hydrazine hydrate as a green hydrogen source. The synthesis of the biogenic NPs has been done using green tools and displays excellent magnetic properties, which have been proved by vibrating sample magnetometry (VSM). Further, field‐emission scanning electron microscopy (FE‐SEM), Fourier transform infrared spectroscopy (FTIR), energy dispersive X‐ray spectroscopy (EDX), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET), have been used for characterization of the synthesized magnetic Fe 3 O 4 @ RA NPs. TEM and XRD analysis revealed the crystalline nature and size of the Fe 3 O 4 @ RA NPs as 10.8 nm. The BET surface area and total pore volume of the Fe 3 O 4 @ RA NPs were observed as 147.098 m 2 /g and 0.323837 cc/g, respectively. VSM analysis displayed super paramagnetic behavior of the NPs and hence reused up to six consecutive cycles without compromising its catalytic performance, which was further approved by FTIR of the recycled Fe 3 O 4 @ RA NPs. Wide substrate scope with excellent functional groups tolerance, large‐scale reactions (up to 1 g), and synthesis of the key pharmaceutical drug, paracetamol, are some adding points of Fe 3 O 4 @ RA NPs.