The removal of PFAS by Fe3O4/ZnO@Ag nano-photocatalyst under visible light irradiation

This paper deals with the challenge of pre-and poly-fluoroalkyl substances (PFAS) pollutant removal from the wastewater due to their persistent and stable chemical nature. Firstly, iron oxide/zinc oxide @ silver (Fe₃O₄/ZnO@Ag) as a photocatalyst was synthesized by a sol–gel method and its morphology and purity were also evaluated by FESEM, XRD, and EDS analyses. Due to the high cost of using UV light and TiO₂, the Ag and ZnO were utilized to reduce it because the ZnO does not have a proper photocatalyst activity under visible light. Based on the mentioned analysis, the purity of the synthesized photocatalyst was confirmed. Response surface methodology is taken into consideration to design the experiments and evaluate the interaction effects. ANOVA results demonstrated the high predictive capability of the model. The results confirmed that by using 0.3 g Ag and enhancing the photocatalyst activity of Fe₃O₄/ZnO, the amount of PFAS was reduced by 87.37% at the pH of 3. Considering the difficulty of PFOS removal, the use of this process can bring very effective results. Due to the low price of zinc oxide compared to titanium oxide and the lower price of the fluorescent lamp compared to the ultraviolet lamp, this process can result in low costs.