Biomimetic fabrication of g-C3N4/TiO2 nanosheets with enhanced photocatalytic activity toward organic pollutant degradation

• Photocatalysts of g-C3N4/TiO2 nanosheets was synthesized by a facile biomimetic method for the first time.
• Heterojunction between TiO2 and g-C3N4 promotes the separation of photo-generated carriers.
• The large surface area of nanosheets and small size of TiO2 nanoparticle improve the photoactivity.
• The synthetic procedure of g-C3N4/TiO2 nanosheets was illustrated.

A facile and efficient approach was first developed to prepare g-C3N4/TiO2 nanocomposites by combining the arginine-enabled biomimetic mineralization of TiO2 with the thermal oxidation etching of bulk g-C3N4. The resultant g-C3N4/TiO2 nanocomposites exhibit a well-defined morphology, in which TiO2 nanoparticles about 5.5 nm in diameter are uniformly distributed on the g-C3N4 nanosheet. They exhibit higher degradation efficiency for Rhodamine B (RhB) than TiO2, g-C3N4 and their mixture under visible light and simulated-sunlight irradiation. In all the as-prepared samples, the g-C3N4/TiO2 nanosheet with 25.9 wt% of g-C3N4 exhibits the highest photocatalytic efficiency, which can degrade almost all RhB under simulated-sunlight irradiation within 50 min. The synergistic effect between TiO2 and g-C3N4 plays an important role for the enhanced photocatalytic activity of g-C3N4/TiO2 nanosheets. This kind of sheet-like nanocomposites may find the potential application for the photocatalytic degradation of organic pollutants.