Mo-oxygen vacancy Co-regulation in Ag3PO4: Band alignment and adsorption optimization for high-efficiency photocatalytic water remediation

To address the bottlenecks of low photocatalytic activity and poor stability in Ag₃PO₄, this study proposes a dual-defect synergistic modulation strategy by simultaneously incorporating Mo doping and oxygen vacancies (OVs) into the Ag₃PO₄ lattice. Systematic hybridization of experimental characterizations and density functional theory (DFT) simulations demonstrates that Mo²⁺ substitution at Ag⁺ lattice sites induces distinctive intermediate states, effectively red-shifting the optical absorption edge to the near-infrared region (700 nm). Concurrently, oxygen vacancies within the bulk phase function as electron scavengers, extending carrier lifetime to 13.5 ns through dynamic charge delocalization. At the atomic interface, surface-anchored OVs regulate local charge distribution, enabling directed OH⁻ migration to Ag active sites and significantly reducing the kinetic barrier for • OH radical formation. The optimized 2 %Mo-Ag₃PO₄ exhibits exceptional visible-light-driven tetracycline mineralization, achieving 93 % degradation efficiency within 30 min while retaining 83 % activity over five catalytic cycles. Band structure modulation ensures a valence band hole (+2.41 V)-dominated h⁺/ • OH degradation pathway. This study establishes a theoretical framework and technical paradigm for dual-defect cooperative optimization in photocatalyst design.