Sono-synthesis of Novel Magnetic Nanocomposite (Ba-α-Bi2O3-γ-Fe2O3) for the Solar Mineralization of Amoxicillin in an Aqueous Solution

In this study, a novel magnetic nanocomposite (Ba-α-Bi2O3-γ-Fe2O3) was successfully synthesized through a combination of ultrasound and co-precipitation method under mild conditions. The structure of the synthesized nano-composite as a visible light photocatalyst was investigated by the XRD, TEM, HRTEM, UV-vis and FT-IR. The HRTEM confirmed that the nano-magnetic composites are rods with diameters of 10–12 nm and lengths of 100–200 nm. The photocatalytic activities of Ba-α-Bi2O3-γ-Fe2O3, α-Bi2O3-γ-Fe2O3, α-Bi2O3, and γ-Fe2O3 were compared by the degradation efficiency of amoxicillin as an antibiotic drug under solar light. Based on the results, amoxicillin in aqueous solution was more efficient photodegraded using Ba-α-Bi2O3-γ-Fe2O3 as nanocomposite under solar light irradiation. The degradation reached to 99% and the mineralization reached to 55% within 2 h under sunlight. In addition, the results of degradation were fitted to the first-order kinetics model and the kinetic constant was 0.017 min-1 with a half-life time of 40 min. Based on the performed experiments, the photogenerated electrons played an important role in the decomposition process. In addition, it was confirmed that the formation of oxidative kinds, such as singlet oxygen and superoxide radical in the presence of oxygen were the major factors in the destruction.