Ultrasound-assisted green synthesis of single phase Fe3O4 nanoparticles and its photocatalytic study for tetracycline photooxidation

Presently, Fe3O4 nanoparticles with high photocatalytic activity were prepared using the ultrasound -assisted green synthesis method using Tagetes erecta flower extract. A single phase Fe3O4 nanoparticles is wellrecognized by physicochemical characterization utilizing x-ray diffraction (XRD), transmission electron microscopy (TEM), and x-ray photoelectron spectroscopy (XPS). Morphological study using scanning electron microscopy (SEM) on the material showed a flower-like shape of the nanoparticles. The particle's size distribution analysis recognized a mean particle size of 29.9 nm. Further study using diffuse reflectance UV-Visible spectroscopy (UV -DRS) gave the band gap energy of 2.68 eV, and VSM analysis has revealed the purity of the nanoparticles that support its feature as magnetic separability as easy method for reusability. The features support the photocatalytic applications as the nanoparticles was demonstrated by fast removal of tetracycline at varied concentration (5-40 mg/L). The highest value of degradation efficiency was 99.9 % expressed by the treatment to 10 mg/L of tetracycline. Mechanistic studies of photooxidation including the effect of pH and photocatalyst stability, suggested the potency of synthesized Fe3O4 nanoparticles as low-cost method for environmental applications.