Deposition of ZnO flowers on the surface of g-C₃N₄ sheets via hydrothermal process

A one pot hydrothermal process was used to grow zinc oxide (ZnO) flowers on the surface of graphitic carbon nitride (g-C₃N₄) for use as an efficient photocatalyst. ZnO flowers on g-C₃N₄ were grown by heat treating a solution of ZnO precursors with g-C₃N₄ particles at 140 °C for 2 h. The resulting composite photocatalyst was characterized by using field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and photoluminescence (PL) spectroscopy. The resulting composites exhibited sheet like g-C₃N₄ decorated with flower-like ZnO microparticles. The composite particle showed much better activity for the photocatalytic degredation of methylene blue than those of g-C₃N₄ or ZnO alone. This enhanced photocatalytic activity of the g-C₃N₄/ZnO composite is attributed to the synergistic effects between g-C₃N₄ and ZnO, which enhance the efficiency of charge separation and reduce the recombination probability of photogenerated electron-hole pairs. The photocatalytic activity of as-synthesized particles did not change after multiple cycles, indicating that the composite was stable and could be reused.