Deriving an α-Fe2O3/g-C3N4 nanocomposite from a naturally hematite-rich soil, for dual photocatalytic and photo-Fenton degradation of Acetaminophen under visible light

In this study, a facile synthesis route was reported for the fabrication of an alpha-Fe2O3@g-C3N4 (FeCN) photocatalyst, derived from a hematite-rich soil. Among the various as-made catalysts prepared using different weights of hematite, FeCN-0.5 showed the best catalytic performance in Acetaminophen (ACT) degradation under visible light irradiation with high mineralization efficiency. The superb activity of this photocatalyst results from a Z-scheme structure formation between alpha-Fe2O3 and g-C3N4 that increased the light adsorption capacity, facilitated the generation of charge-carries, and increased the generated electrons that participated in Fe3+/Fe2+ cycles, thus enhancing the photo-Fenton reaction. UV-Vis diffuse reflection spectroscopy (DRS) and photoluminescence analysis (PL) confirmed the excellent separation of charge carriers in the as-made photocatalyst. The reaction rate of the FeCN-0.5/Vis/H2O2 process was around 3, and 7 times of that in the FeCN-0.5/Vis and FeCN-0.5/H2O2 processes respectively, which indicated the synergy effect of the involved processes in ACT degradation. Based on the radical trapping experiments, hydroxyl radical (HO center dot) was the dominant reactive species in ACT degradation. The catalyst showed high stability in consecutive reuse cycles. Overall, this study provides new insights into the fabrication of novel materials derived from natural sources, suitable for their use in advanced oxidation processes.