Adsorption of brilliant green dye by iron oxide nanoparticles synthesized from the leaf extracts of Acacia jacquemontii.

Phyto-mediated synthesis can be used for the sustainable fabrication of metallic nanoparticles (NPs). Ethanolic leaf extract of Acacia jacquemontii was used to phyto-fabricate iron oxide nanoparticles (FeO NPs). Synthesized FeO NPs were examined by various analytical techniques for their detailed chemical elemental and morphological features. High-performance thin-layer chromatography (HPTLC) was used for the analysis of the ethanolic extracts of the leaves, which ensured the presence of phenols and terpenoids in the extract. FeO NPs show a peak between 350-400nm when analyzed by UV-Vis spectroscopy, and the typical bands were found in the range of 745 cm^-1 for Fe-O and 1595 cm^-1, 3177 cm^-1 for some other organic molecules by Fourier transform-infrared (FTIR). The spherical shape of FeO NPs was investigated with the help of a Field emission scanning electron microscope (FESEM) analysis which exhibited the size varied from 13.35 to 31.29 nm. Electron diffraction spectroscopy (EDS) confirmed the Fe, O, and C peaks, along with N, Cl, S, and K traces. The adsorption capacity of the FeO NPs for brilliant green (BG) dye was evaluated at different pH, dosages of adsorbent, and contact time. The highest adsorption parentage of 57.2% for 10 ppm BG dye was observed at 9 pH and 10 mg doses of FeO NPs. The highest absorption capacity of FeO NPs is 60 mg/g. The recyclability potential of the FeO NPs continuously decreased with the repletion of the cycle from first to fourth whose value reached 19.33% after the fourth cycle. Such phytofabricated FeO NPs and their application in the removal of organic could prove to be eco-friendly and economical.