S-scheme g-C₃N₄/Ce₂S₃ nanocomposites for visible-light activation of persulfate ions: Photocatalytic degradations of antibiotics and dyes

An S-scheme g-C₃N₄/Ce₂S₃ photocatalyst (abbreviated as CN/Ce₂S₃) was constructed through a facile hydrothermal method, and used to activate persulfate ions (PS). The CN/Ce₂S₃ (20 %) nanocomposite exhibited superior photocatalytic performance in removing three antibiotics, including tetracycline (TC), amoxicillin (AMX), azithromycin (AZT), and three dye contaminants, containing methyl orange (MO), methylene blue (MB), and rhodamine B (RhB) upon visible light. The XPS, EDX, XRD, and HRTEM analyses indicated the successful combination of CN and Ce₂S₃ semiconductors. The photoactivity of CN/Ce₂S₃ (20 %)/PS system for removing TC was about 51.0, 26.6, and 1.96-fold premier than the PS, CN/PS, and CN/Ce₂S₃ (20 %) samples, respectively. Besides, the recycled photocatalyst demonstrated remarkable activity even after four recycling applications. The surprising performance of the CN/Ce₂S₃ (20 %)/PS system was related to the impressive surface area, extended light absorption, and facile charges separation/transfer. Finally, the biocompatibility of the contaminated solution after the photocatalytic reaction was affirmed through the growth of wheat seeds. Accordingly, the S-scheme CN/Ce₂S₃ photocatalyst can be considered a promising material for the detoxification of the environment.