Preparation and development of FeS Quantum Dots on SiO nanostructures immobilized in biopolymers and synthetic polymers as nanoparticles and nanofibers catalyst for antibiotic degradation.

The FeS Quantum Dots (QDs) decorated SiO nanostructure were prepared by hydrothermal synthesis method. Chitosan and polypyrrole as polymers were used for the immobilization process. The characteristic structure of prepared samples was analyzed using several techniques such as X-ray diffraction, scanning and transmittance electron microscopy, photoluminescence and UV-vis spectroscopy. The mean crystallite sizes of FeS QDs/SiO nanocomposites, FeS QDs/SiO-chitosan nanocomposites and FeS QDs/SiO-polypyrrole nanohybrids are 56.12, 76.38, and 83.24nm, respectively. The band gap energy of FeS QDs/SiO nanocomposites, FeS QDs/SiO-chitosan nanocomposites and FeS QDs/SiO-polypyrrole nanohybrids were found out to be 3.0, 2.8, and 2.7eV, respectively. The photocatalysis properties were investigated by degradation of ampicillin under UV light illumination. The effect of experimental variables, such as, pH and time, on photo-degradation efficiency was studied. The results show that the three prepared samples nanopowders under UV light was in pH3 at 60min. As it could be seen that the amount of ampicillin degradation was increased with the loading of FeS QDs on SiO and FeS QDs/SiO on chitosan nanoparticles and polypyrrole nanofiber. The antibacterial experiment was investigated under visible light illumination and the FeS QDs/SiO-chitosan nanocomposites and FeS QDs/SiO-polypyrrole nanohybrids demonstrate good antibacterial compared to FeS QDs/SiO nanocomposites.