Photodegradation of Polycyclic Aromatic Hydrocarbons Under Visible Light Using Modified g-C3N4 as Photocatalyst, Spectroscopic Studies

Abstract

In this work, visible light was used for the photodegradation of polycyclic aromatic hydrocarbons (PAHs) using graphitic carbon nitride (g-C₃N₄) and it was modified as a photocatalyst. Modification of g-C₃N₄ was performed using SDS, MIL-101, and TiO₂. The UV–Vis spectroscopy, XRD, and FTIR spectrometry were applied for characterization. The photodegradation of pyrene and anthracene was investigated using the photocatalyst. Results indicated that the modified photocatalytic has better photocatalytic properties than that unmodified due to the more surface area and better optical properties of the former_. Results also revealed that the photodegradation efficiency significantly improved by using g-C₃N₄@TiO₂ so that it degrades about 95% of the pyrene molecules within 12 h. While g-C₃N₄@ SDS and g-C₃N₄@ MIL-101 are degraded very low (below 10%) under the same circumstances. The LED lamp (8 W) was used as a source of radiation. Photodegradation of anthracene was also investigated; results revealed that the anthracene is degraded more quickly than the pyrene, so that after 6 h about 98% of anthracene is decomposed. The mechanism of photodegradation was discussed.