Dual Z-scheme heterojunction CeSnO/AgPO/V@g-CN for increased photocatalytic degradation of the food additive tartrazine, in the presence of persulfate: Kinetics, toxicity, and density functional theory studies.

This study involved the synthesis of a CeSnO/AgPO/V@g-CN composite through hydrothermal methods, followed by mechanical grinding. The resulting heterojunction exhibited improved catalytic activity under visible light by effectively separating electrons and holes (e/h). The degradation of Tartrazine (TTZ) reached 93.20% within 50 min by employing a ternary composite at a concentration of 10 mg L, along with 6 mg L of PS. The highest pseudo-first-order kinetic constant (0.1273 min and R = 0.951) was observed in this system. The dual Z-scheme heterojunction is developed by CeSnO, AgPO, and V@g-CN, and it may increase the visible light absorption range while also accelerating charge carrier transfer and separation between catalysts. The analysis of the vulnerability positions and degradation pathways of TTZ involved the utilization of density functional theory (DFT) and gas chromatography-mass spectrometry (GC-MS) to examine the intermediate products. Therefore, CeSnO/AgPO/V@g-CN is an excellent ternary nanocomposite for the remediation of pollutants.