Facile and rapid synthesis of solar-driven TiO2/g-C3N4 heterostructure photocatalysts for enhanced photocatalytic activity

Abstract

TiO2 has been successfully coupled with graphitic carbon nitride (g-C3N4) using the thermal deposition method to create an advanced heterojunction photocatalyst. The prepared photocatalysts were studied for photocatalytic hydrogen production and methylene blue dye degradation. The synthesized materials were thoroughly characterized by XRD, XPS, FT-IR, HR-TEM, UV-Vis DRS, and Photoluminescence studies. The results obtained clearly confirm that the photocatalytic efficiency of TiO2 is significantly enhanced after making the nanocomposite with g-C3N4 nanostructures. The hydrogen production rate under simulated sunlight irradiation for a TiO2/g-C3N4 heterojunction photocatalyst has been obtained at approximately 110 μmolg−1h−1. Trapping tests of active species during photocatalysis clearly revealed that O2•‒ played a critical role to enhance the activity. It is significantly proved that the enhancement in the photocatalytic activity is due to the interfacial contact between the TiO2 and g-C3N4, which effectively reduces the electron hole recombination. Eventually, the influence of bandgap energies and their band edge potentials were discussed by proposing a well defined schematic mechanism.

Keywords

• TiO2/g-C3N4
• Hydrogen production
• Heterojunction photocatalyst
• Methylene blue degradation