Degradation of Tetracycline in Medical Wastewater by Fe 2 O 3 /CuO Photocatalyst Under Visible Light

To explore the development of photocatalytic materials which were highly efficient, nonpolluting, have low production cost and are recyclable for degrading tetracycline (TC) in medical wastewater. In the study, Fe 2 O 3 was selected as the photocatalyst, and CuO was introduced to modify it to produce the Fe 2 O 3 /CuO photocatalyst. The Fe 2 O 3 /CuO composite photocatalysts were investigated by characterization means such as XRD, SEM, UV–Vis DRS and EPR. The enhanced photocatalytic activity of the Fe 2 O 3 /CuO was attributed to CuO doping, which modulates the band structure, creating a new bandgap that extends the absorption spectrum and improves the utilization of visible light. Additionally, Fe 2 O 3 serves as an electron donor, significantly accelerating the separation of photogenerated electron–hole pairs. The effects of doping ratio, dosage, initial concentration of TC and illumination time on the degradation of TC in medical wastewater by Fe 2 O 3 /CuO composite photocatalysts were investigated. Under the optimized conditions, the degradation rate of TC by the Fe 2 O 3 /CuO photocatalyst was 94.26%. The removal rate of the loaded Fe 2 O 3 /CuO-4 photocatalyst remained above 90% after five repetitions. The Fe 2 O 3 /CuO-4 photocatalyst was suitable for practical application in the treatment of antibiotics in medical wastewater due to its simple preparation and good photocatalytic ability, and reusability.