Decomposition of microplastics using copper oxide/bismuth vanadate-based photocatalysts: Insight mechanisms and...

To mitigate marine pollution, we improved the photo-Fenton reaction of modified nanoscale CuO/BiVO₄ photocatalysts to resolve the challenge of efficient microplastic degradation in wastewater treatment. Material property analysis and computational results revealed that deposition of CuO onto BiVO₄ nanocomposites improved photocatalytic activity by promoting an excess of electrons in CuO and surface charge transfer, resulting in an increased production of e^--h⁺ for ROS generation via H₂O₂ activation. ¹O₂ was dominated and identified through quenching experiments, XPS analysis, and EPR. ROS generation increased via H₂O₂ activation, causing major surface abrasion and increased carbonyl and vinyl indices in microplastics. Treated water had minimal impact on Lycopersicon esculentum Mill. seedling growth but caused considerable mortality in cell lines and Moina macrocopa mortality at greater dosages due to their sensitivity to ions and H₂O₂ residuals. Overall, this treatment can effectively degrade microplastics, but the dilution of treated water is still needed before being discharged.