Facile synthesis of iron oxide nanoparticles using Cassia auriculata flower extract and accessing their photocatalytic degradation and larvicidal effect

The present study validates the green synthesis of iron oxide nanoparticles (IONPs) using aqueous extract of Cassia auriculata (CA) flower. The green-synthesized Cassia auriculata iron oxide nanoparticles (CA-IONPs) were characterized by UV–Vis spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, Field emission scanning electron microscope (FESEM) with Energy dispersive X-ray spectroscopy (EDX), Transmission electron microscopy (TEM), X-ray diffraction (XRD), and vibration sample magnetometer (VSM). The UV–Vis spectra of CA-IONPs revealed a broad absorption peak at 370 nm, and FT-IR represented the presence of bioactive functional groups. The results of XRD and VSM confirmed the crystalline nature and magnetic properties of CA-IONPs. FESEM result proves the spherical shape of CA-IONPs and existence of iron at 7.0 keV through EDAX. The Brunauer–Emmett–Teller (BET)-specific surface area of biosynthesized IONPs was recorded as 1.48 m 2 /g. The photocatalytic efficiency of CA-IONPs against methyl green showed 91.2% decolorization within 150 min of visible-light irradiation. In addition, the CA-IONPs showed good larvicidal potential against dengue vector Aedes aegypti. Thus, the green-synthesized CA-IONPs confirmed to be a potential substance for environmental remediation and control the mosquitoes.