Preparation of eco-friendly nanocomposites from nano metal oxides with conducting polymer for enhancing catalytic degradation of petroleum pollutants from industrial wastewater

Abstract

In this study, novel PANI/WO3,PANI/ZnO, PANI/WO3@ZIF-8, PANI/ZnO@ZIF-8, PANI/WO3@UiO-66-NH2 and PANI/ ZnO @UiO-66-NH2 photocatalysts were successfully synthesized and characterized using XRD, FT-IR, FESEM, TEM, EDX, BET, UV–vis and PL techniques. Under optimal conditions, the photodegradation of 4-nitrophenol (20 mg/L) was examined as a model of petroleum pollutants in heterogeneous systems under visible light irradiation. The prepared nanocomposites showed superior photocatalytic activities toward 4-nitrophenol degradation with visible light irradiation (degradation efficiency~100%). The remarkable improvement of catalytic activity and photostability could be due to the synergetic effect between WO3, ZnO, PANI, and MOFs. Typically, 20 ppm of the 4-NP solution was degraded completely and 95.8% of the carbon content had been mineralized in 180 min at 25 °C using 0.5 g/L of the PANI/WO3@UiO-66-NH2 nanocomposite. Based on the quenching tests, •OH and •O2- were referred to be the main active species. Reusability experiments of photocatalysts demonstrated that the photocatalysts display excellent stability and reusability.