Supplementary material from "Multifunctional Fe3O4 Modified ZnO Dual Phase Nanostructure for Photocatalytic, Antibacterial, and Antioxidant activities"

In this study, Fe3O4 (F), ZnO (Z), and Fe3O4@ZnO (FZ) nanomaterials were synthesized using leaf extract as a reducing and stabilizing agent. Characterization was performed using TGA-DTA, FTIR, XRD, BET, SEM, HRTEM, DRS, and PL techniques. The FZ (2:1) composite showed the smallest crystallite size (18 nm), modified band gap (2.46 eV), and highest surface area (97 m2/g), suggesting strong catalytic and antibacterial potential. The photocatalytic activity of the synthesized materials against methylene orange (MO) was evaluated, achieving maximum efficiency (96%) for FZ (2:1) and minimum efficiency (76%) for F nanoparticles. Furthermore, the antibacterial activities of F and FZ (2:1) materials against Enterococcus faecalis and Escherichia coli were assessed. At 100 µg/mL, inhibition zones of 23.00 ± 0.58 mm for E. faecalis and 21.67 ± 0.24 mm for E. coli were obtained with the composite. These values represent improvements of 38% and 44.5%, respectively, compared to Fe3O4 nanoparticles, which exhibited inhibition zones of 16.67± 0.49 mm and 15.00 ± 0.56 mm. Likewise, the antioxidant activities of F and FZ (2:1) were evaluated, with maximum inhibition percentages of 66.31% and 89.32%, respectively, at 100 µg/mL. Overall, the results indicate that the FZ (2:1) composite exhibits remarkable efficiency among the synthesized materials.