The unforeseen relationship of Fe2O3 and ZnO on fibrous silica KCC-1 catalyst for fabricated Z-scheme extractive-photooxidative desulphurization

Abstract

Fibrous silica KAUST Catalysis Centre (KCC-1) was prepared via a hydrothermal-microwave method, followed by incorporation of Fe2O3 and ZnO by an electrochemical technique to give ZnO-Fe2O3/KCC-1 (ZFK) catalysts. XRD, FESEM, N2 physisorption, FTIR, XPS, ESR and UV–Vis DRS were employed to characterize the catalysts. A varied amount of Fe2O3 and ZnO seems have insightful impact on the physicochemical behaviours of the KCC-1 while prominently enhanced the extractive-photooxidative desulphurization of dibenzothiophene (DBT). 5Z10FK demonstrated the best performance mainly due to a well distribution of both metal oxides on KCC-1, the highest Si-O-Fe and Si-O-Zn bonds, an appropriate amount of surface defect and suitable band gap energy. Besides, the suitable band positions of 10FK and 5ZK in 5Z10FK composite has allowed the formation of Z-scheme heterojunction for conserved strong redox potential. Kinetic studies revealed that the adsorption of DBT was the rate determining step, thus this reaction obeyed the Langmuir-Hinshelwood pseudo-first order.