A novel magnetic NiFe2O4-Ag-ZnO hybrid nanocomposite for the escalated photocatalytic dye degradation and antibacterial activities

Abstract

The eco-friendly and cost-effective NiFe2O4-Ag-ZnO (nickel ferrite-silver-zinc oxide) (NFAZnO) nanocomposite was made using an easy straightforward chemical co-precipitation method and subsequent thermal treatment process. The increased UV light-driven photocatalytic performance and enhanced antibacterial activity of the nanocomposite were reported. The structural, morphological, magnetic, and catalytic characteristics of the nanocomposite were characterized by using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR), photoluminescence (PL), Raman, vibrating-sample magnetometry (VSM), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET) analysis. The results from XRD revealed that NFAZnO has a crystalline structure and EDAX elemental mapping confirmed the uniform distributed of all the elements in the matrix. Investigations into the microstructure found ultrafine grained structure of NFAZnO nanocomposite with an average crystallite size of 27.95 ± 0.38 nm as calculated from Scherrer’s formula. NFAZnO nanocomposite has a specific surface area of 13.56 m2/g, which is significantly more than ZnO (6.89 m2/g) as calculated from BET. At normal temperature, the magnetic characteristics showed the superparamagnetic behavior of the nanocomposite with saturation magnetization (Ms) value of 6.59 emu/g, remnant magnetization (Mr) value of 0.75 emu/g, and coercive field (Hc) value of 170 Oe. The Ag doping and addition of NiFe2O4 induces depletion in near-band edge emission, which lowers the rate of electron-hole recombination, according to the PL observations. Methylene Blue (MB) dye was subjected to photocatalytic degradation under the exposure to UV light, and according to the findings, NFAZnO nanocomposite exhibited the highest levels of photocatalytic activity with 98% degradation in just 60 min. The NFAZnO nanocomposite also showed enhanced antibacterial activity against Escherichia coli (E. coli) having zone of inhibition (ZOI) of about 28.9 ± 0.28 mm showing 123.5% activity as compared to control ampicillin having ZOI of 23.4 ± 0.13 mm, proving its applicability for both biomedical and environmental applications.