Z-scheme BiPO4/Bi2Fe4O9 heterojunction as visible-light-driven peroxymonosulfate activator for enhanced tetracycline degradation and toxicity risk reduction

In order to effectively degrade tetracycline (TC), a novel B i PO 4 / B i 2 F e 4 O 9 photocatalytic composite was created in this study. When compared to several bismuth-based photocatalytic materials, the system demonstrated excellent degradation activity. PMS is activated under visible light irradiation. System B i PO 4 / B i 2 F e 4 O 9 /PMS/Vis removes 89.3% of TC in 60 minutes. Based on the energy band structures of B i 2 F e 4 O 9 and B i PO 4 , the catalytic efficiency of the composites could be explained by type Z heterojunction mechanism. Superoxide radicals and holes are the primary causes of TC degradation, as shown by experiments using electron paramagnetic resonance and free radical entrapment. In addition, the system B i PO 4 / B i 2 F e 4 O 9 /PMS/Vis maintained its high degradation capacity and pristine composition after multiple recycling. The reaction system's TC degradation was not considerably impacted by pH, anions, or ionic strength. The TC degradation intermediates demonstrated a noteworthy decrease in toxicity within the BPFO-10/PMS/Vis system, hence guaranteeing the intermediates' safe conversion. These findings highlight the significant potential of the novel bismuth-based photocatalytic composite for degrading emerging pollutants in wastewater.