Mo-doping engineered BiVO4 in a Bi2WO6/NH2-UiO-66 heterostructure: Boosting charge separation for efficient antibiotic removal

The growing prevalence of antibiotic residues in aquatic environments, particularly recalcitrant antibiotics like tetracycline (TC), poses significant ecological risks. In this study, a novel Bi 2 WO 6 /Mo-doped BiVO 4 /NH 2 -UiO-66 (BBU) ternary heterojunction photocatalyst was successfully synthesized via a solvothermal method to enhance visible-light-driven TC degradation through component synergy. Systematic characterization revealed that Mo doping induced lattice distortion in BiVO 4 , while the incorporation of NH 2 -UiO-66 drastically increased the specific surface area from 23.647 to 398.804 m 2 ·g −1 , providing abundant active sites. Photoluminescence (PL) and Electrochemical Impedance Spectroscopy (EIS) analyses demonstrated that the optimized BBU-3 sample exhibited the lowest charge carrier recombination rate. Under visible light irradiation for 80 min, BBU-3 achieved 95.2% degradation of TC, with reaction kinetics 8.61, 15.76, and 5.01 times higher than those of pristine Bi 2 WO 6 , BiVO 4 , and binary heterojunctions, respectively. Degradation-trapping experiments and electron paramagnetic resonance (EPR) measurements indicate that h + , 1 O 2 and ·O 2 - are the primary reactive species, suggesting that this system is a synergistic radical-non-radical degradation system. Additionally, possible degradation pathways and intermediate toxicity were evaluated. This work offers a promising strategy for designing efficient bismuth-based MOF heterojunctions for antibiotic remediation in water.