Visible-light-driven CuV₂O₆/BiPO₄/GO ternary heterojunctions for efficient degradation of organic water pollutants

This study develops a novel ternary CuV₂O₆/BiPO₄/GO photocatalyst via hydrothermal synthesis to address organic water pollution. The composite forms an n-n heterojunction enhancing visible-light absorption (bandgap: 1.95-4.10 eV) and charge separation. Systematic characterization (XRD, SEM, XPS, and UV‒Vis DRS) confirmed that the CuV₂O₆ nanoparticles anchored on BiPO₄ with GO facilitated charge transport. Under visible light at neutral pH, the optimized composite achieved 95.7% methylene blue (MB) degradation in 30 min and 92.2% moxifloxacin (MOX) removal in 42 min, representing 7.1-fold and 18.1-fold improvements over pure BiPO₄, respectively. Radical trapping identified superoxide radicals (O₂^-) as the primary active species. The synergistic mechanism involves (1) CuV₂O₆ extending light absorption, (2) heterojunction-driven charge separation, and (3) a conductive network of GO boosting electron transfer. Photoelectrochemical tests (PL and EIS) validated the suppressed recombination and reduced charge transfer resistance. This work provides a high-performance, solar-driven solution for water purification and insights into ternary heterojunction design.