Construction of magnetic recoverable CoFe2O4/Mn0.5Cd0.5S heterojunction for photocatalytic hydrogen evolution and tetracycline degradation

To investigate the hydrogen evolution performance of Mn 0.5 Cd 0.5 S (MCS) under visible light and its degradation effect on tetracycline, this study prepared MCS and CoFe 2 O 4 (CFO) photocatalysts via the hydrothermal method. Specifically, MCS was synthesized using manganese acetate as the Mn source, cadmium acetate as the Cd source, and thioacetamide as the S source, while CFO was prepared using cobalt nitrate and iron nitrate as precursors. The composite material CFO/MCS was fabricated via an ultrasound and calcination method for photocatalytic hydrogen evolution and tetracycline degradation. The results demonstrated that the CFO/MCS-24 % composite exhibited the best catalytic performance. Under a 10 W light source for 5 h, the maximum hydrogen evolution reached 401 μmol, with AQE of 0.15 % at a wavelength of 450 nm. Additionally, CFO/MCS-24 % degraded 88 % of tetracycline within 120 min. Based on XPS spectra analysis, DFT calculations, and the conduction and valence band positions of CFO and MCS, it is speculated that Z-scheme heterojunction is formed between them. The successful preparation of CFO/MCS not only significantly enhanced the catalytic activity of the photocatalyst but also enabled the recycling of the nanocatalyst, providing a valuable reference for the application of composite materials in photocatalysis.