Oxygen vacancies boosting peroxymonosulfate activation on 1D/2D CuBi2O4/Bi2MoO6 for rapid antibiotic removal and harmful cyanobacterial inactivation: Dual active site regulation and synergistic pathway insights

Antibiotics exacerbate harmful algal blooms (HABs), seriously threatening water safety. Photocatalytic activation of peroxymonosulfate (PMS) for organic pollutant degradation has emerged as a promising green strategy for environmental remediation. However, developing efficient catalysts with strong interfacial effects and abundant active sites faces significant challenges. Herein, an oxygen vacancy-enriched 1D/2D CuBi₂O₄/Bi₂MoO₆ heterojunction was synthesized for visible-light-driven PMS activation, enabling efficient various antibiotics degradation and Microcystis aeruginosa inactivation. The unique 1D/2D heterostructure, surface OVs, and Cu²⁺/Cu⁺ redox cycling facilitated strong interfacial contact and spatial charge separation. Within 30 min, the degradation and mineralization rates of tetracycline (TC) reached 98.9 % and 65.4 %, respectively, while the system rapidly inactivated Microcystis aeruginosa, with an inactivation rate of 88.7 % and chlorophyll a removal rate of 91.3 %. Moreover, t the system overcame the ion leaching issue associated with conventional transition metal activator PMS processes, and the synergy between OVs and Cu dual active sites enhanced material stability, environmental tolerance, and broad applicability. In situ experiments and DFT calculations revealed that the internal electric field and Cu–O-Mo electron bridge triggered the S-scheme charge transport and promoted strong redox reactions. OVs and Cu dual active sites served as additional centers for pollutant adsorption and PMS activation, accelerating electron transfer and O-O bond cleavage, enhancing the synergistic effects at the heterogeneous interface. LC-MS and reactive site identification elucidated degradation pathways and algicidal mechanisms. This work provides valuable insights for designing OVs and metal sites modulated heterojunctions for PMS activation in water purification.