Degradation of Emerging Plastic Pollutants from Aquatic Environments Using TiO and Their Composites in Visible Light Photocatalysis.

This review synthesized the current knowledge on the effect of TiO photocatalysts on the degradation of microplastics (MPs) and nanoplastics (NPs) under visible light, highlighting the state-of-the-art techniques, main challenges, and proposed solutions for enhancing the performance of the photocatalysis technique. The synthesis of TiO-based photocatalysts and hybrid nanostructured TiO materials, including those coupled with other semiconductor materials, is explored. Studies on TiO-based photocatalysts for the degradation of MPs and NPs under visible light remain limited. The degradation behavior is influenced by the composition of the TiO composites and the nature of different types of MPs/NPs. Polystyrene (PS) MPs demonstrated complete degradation under visible light photocatalysis in the presence of α-FeO nanoflowers integrated into a TiO film with a hierarchical structure. However, photocatalysis generally fails to achieve the full degradation of small plastic pollutants at the laboratory scale, and its overall effectiveness in breaking down MPs and NPs remains comparatively limited.