Preparation of AgBr/Ag3PO4/GdFeO3 composite photocatalyst and its high-efficiency photocatalytic performance in degradation of norfloxacin

Abstract

The antibiotic contamination in water bodies poses a serious threat to human health and ecological balance, and urgent measures are needed to purify it. In this study, a novel AgBr/Ag₃PO₄/GdFeO₃ composite photocatalyst was prepared via ultrasound dispersion method, and it was used for the photocatalytic degradation of antibiotics such as norfloxacin(NOR) in water. Under optimal conditions, the degradation rate of 20 mg/L NOR by AgBr/Ag₃PO₄/GdFeO₃ reached 82.94 %, demonstrating superior photocatalytic activity compared to AgBr, Ag₃PO₄, GdFeO₃, and AgBr/Ag₃PO₄, and it also has good stability for repeated use and wide applicability. The relevant characterization results reveal that the main reason for the enhanced photocatalytic activity of AgBr/Ag₃PO₄/GdFeO₃ is that the combination of AgBr and GdFeO₃ with Ag₃PO₄ enhances its visible light response capability, increases its surface area, and constructs a dual Z-scheme heterojunction. Furthermore, the wheat seedling bioassay indicated that the photodegraded NOR solution exhibited a marked reduction in phytotoxicity. Finally, a dual Z-scheme electron transfer mechanism of AgBr/Ag₃PO₄/GdFeO₃ was proposed, along with several possible pathways for the photocatalytic degradation of NOR. This study provides new insights for the improvement of Ag₃PO₄-based photocatalyst and offers a new reference for the treatment of wastewater containing NOR.