Efficient degradation of RhB by Fe-N-TiO₂ through photocatalytic synergistic persulfate system

In order to achieve efficient degradation of Rhodamine B (RhB) dye in a short time, Fe and N co-doped TiO 2 photocatalyst (Fe-N-TiO 2 ) was prepared by sol–gel method and used for photocatalytic activation of peroxymonosulfate (PMS) to degrade RhB. SEM-EDS, XRD, and XPS results showed that Fe-N-TiO 2 was successfully prepared. The results of UV–Vis DRS and EIS showed that compared with pure TiO 2 , the modified catalyst showed higher electron transfer efficiency and light absorption ability, which enhanced the electron production ability and activated more PMS to generate free radicals to degrade RhB. The experimental results show that the degradation rate of RhB can reach 85.59% under the PC/PMS system with a PMS concentration of 2.0 mmol L[Formula: see text], catalyst dosage of 0.5 g L[Formula: see text] and pH = 3 for 30 min. In addition, the catalyst has good repeatability and stability, and the degradation rate can still be maintained above 70% after 5 times of continuous use. The results of free radical capture experiments showed that the main active substances in the reaction system were [Formula: see text]OH, SO 4 [Formula: see text], [Formula: see text]O 2 [Formula: see text], and h[Formula: see text], and the possible mechanism of RhB in PC/PMS/Fe-N-TiO 2 -0.5% system was proposed, which provided a theoretical basis for dye wastewater treatment.