Harnessing the power of multifunctional γ-Fe2O3@CuO nanocomposites: Effective extraction of heavy metals and bacterial pathogens from contaminated water

Abstract

Waterborne diseases and carcinogenic effects associated with heavy metal poisoning have drawn considerable attentionto removing heavy metals from contaminated water and killing disease-causing bacteria. In this regard, γ-Fe2O3 nanoparticles (NPs) were synthesized by ion reduction method, while CuO NPsand γ-Fe2O3–CuO nanocomposites (NCs) by hydrothermal method. XRD, FTIR, FESEM, EDX and UV–visible spectroscopy were used for system characterization. The dumbbell shape of CuO NPs and spherical shape of γ-Fe2O3 NPs and γ-Fe2O3@CuO NCs were indicated via SEM analysis. The elemental composition and successful synthesis of γ-Fe2O3@CuONCs were confirmed by EDX results. The order for elemental composition: O > Cu > Fe showed the higher content ratio of Cu and O while Fe has the lowest content. The antibacterial activities against E. Coli and B. subtili were evaluated by Minimum Inhibitory Concentration (MIC) and Zone of Inhibition. γ-Fe2O3@CuO NCs showed excellent antibacterial performance as compared to γ-Fe2O3 NPs,CuO NPs, commercial Cu NPs and Cu salt. The drastic improvement in properties of γ-Fe2O3@CuO NCs resulted in better surface contact and extensive cell membranes rupture to eliminate bacterial pathogens present in wastewater Batch adsorption experiments were performed for selective removal of toxic Pb2+ ionsexisting in polluted water. The greatest adsorption capacity was determined to be 346 mg/g, and the highest removal percentage of 95 % was achieved at pH 4 in 60 min. Isotherm models and kinetic studies indicated that Pb2+ ions followed pseudo-second-order kinetics. The results obtained from batch adsorption experiment revealed γ-Fe2O3@CuO NCs as effective nanosorbent for quick elimination of toxic metal ions from industrial wastewater.