Preparation Method and Application of a p‑n Heterojunction Pt/TiO₂/AgBr/Ag Composite Photocatalyst

Using natural loofah sponge as a template, the catalyst was prepared by loading Pt via alkali treatment, followed by loading TiO₂ and calcination, and finally loading AgBr through ion reaction and ultraviolet irradiation. The dosage of KBr was also optimized.

Experiments verified that the catalyst exhibited excellent degradation performance toward ciprofloxacin: the degradation efficiency reached 86.2% when 40 mg of catalyst was used to treat 50 mL of 5 mg/L ciprofloxacin solution, and its catalytic activity was superior to that of pure TiO₂, AgBr and other materials.