Rice-husk-derived mesoporous 0D/2D C₃N₄ isotype heterojunction with improved quantum effect for photodegradation of tetracycline antibiotics

Synthesis of highly active carbon nitride (C₃N₄)-based photocatalysts with specific structures for antibiotics degradation is a hot research topic in the photocatalysis field. In this study, rice-husk-derived SiO₂ is employed as the sacrificial template to synthesize mesoporous photocatalyst with 0D/2D C₃N₄ isotype heterojunction and improved quantum effect for tetracycline photodegradation. The structures and properties of as-prepared samples are systematically characterized and discussed. Results show that vacuum-assisted ultrasonic treatment is essential for the synthesis of the most active photocatalyst which is consisted of zero dimensional (0D) C₃N₄ quantum dots adsorbed on the two dimensional (2D) C₃N₄ sheets. The 0D/2D C₃N₄ isotype heterojunction combines with the mesoporous structure is effective for transferring the photogenerated electrons and leaving the holes (h⁺), which have higher oxidation potential because of the extended band gap, for effective tetracycline photodegradation under the visible light irradiation.