Magnetic recyclable heterogeneous catalyst FeO/g-CN for tetracycline hydrochloride degradation via photo-Fenton process under visible light.

Antibiotic pollution of water resources is a global problem, and the development of new treatments for destroying antibiotics in water is a priority research. We successfully manufactured recyclable magnetic FeO/g-CN through the electrostatic self-assembly method. Selecting tetracycline (TC) as the target pollutant, using FeO/g-CN and HO developed a heterogeneous optical Fenton system to remove TC under visible light. FeO/g-CN was systematically characterized by SEM, TEM, XRD, FTIR, XPS, DRS, and electrochemical methods. The removal efficiency of 7% FeO/g-CN at pH = 3, HO = 5 mM, and catalyst dosage of 1.0 g/L can reach 99.8%. After magnetic separation, the FeO/g-CN photocatalyst can be recycled five times with minimal efficiency loss. The excellent degradation performance of the prepared catalyst may be attributed to the proper coupling interface between FeO and g-CN which promotes the separation and transfer of photogenerated electrons. Photogenerated electrons can also accelerate the conversion of Fe to Fe, thereby producing more ˙OH. The new FeO/g-CN can be used as a raw material for advanced oxidation of water contaminated by refractory antibiotics.