Z-type heterojunction degradation of tetracycline by 2D g-C3N4 with 3D oxygen vacancy Bi2WO6

Photocatalytic degradation is a promising strategy for environmental remediation. Graphitic carbon nitride (g-C3N4) is the most extensively reported metal-free, Hierarchical flower-shaped Bi2WO6 particles were obtained using a simple hydrothermal method, with petals of flower-like Bi2WO6 with oxygen vacancies (Bi2WO6 OVs) with controlled content successfully decorated on g-C3N4 nanosheets. A novel Z-scheme 2D/3D heterojunction photocatalyst, g-C3N4/Bi2WO6 OVs, was successfully prepared, with its composition and structure studied using a series of material characterization techniques. Compared to single g-C3N4 and Bi2WO6 OVs, the g-C3N4/Bi2WO6 OVs exhibited improved photocatalytic activity for the degradation of tetracycline, with a degradation rate of more than 90%. Moreover, electron paramagnetic resonance spectroscopy, X-ray photoelectron spectroscopy, and Mott–Schottky measurements suggest that a Z-scheme heterojunction formed between the g-C3N4 nanosheets and Bi2WO6 OVs floral forms and that the photoinduced electrons in Bi2WO6 OVs bind to holes in g-C3N4, thus enhancing the extraction and utilization of carriers under photoexcitation. Hence, this study presents an effective method for constructing 2D/3D heterojunctions for solar fuel conversion and photocatalytic water treatment.