Heterogeneous photocatalysis as an efficient process for degrading MPs/NPs in aqueous media: A systematic review

Plastic waste has become one of the most pressing environmental issues due to the resistance of these materials to natural degradation. Over time, they break down into microplastics (MPs) and nanoplastics (NPs), posing a serious problem, especially in water pollution, and can have significant impacts on the quality of human, animal, and plant life. Several emerging strategies are being explored to combat this pollution, with the emergence of semiconductors as effective and sustainable heterogeneous photocatalysts for degrading MPs/NPs. The strategy is promising for tackling this social and environmental challenge. Therefore, this review begins by addressing the systemic issue of MPs/NPs in aquatic environments, emphasizing their occurrence, effects and degradation processes. It then outlines the application of heterogeneous photocatalysis for the degradation of MPs and NPs. In addition, we present some significant recent research into the upcycling approach, which involves transforming plastic waste into chemical inputs with high added value. We then explore the current limitations and future challenges in advancing this field of study. • MPs and NPs significantly impact human, animal, and plant life. • Developing efficient technology against MPs/NPs pollution is still challenging. • Semiconductors as photocatalysts for degrading MPs/NPs. • Value-added chemicals formed from photocatalytic upcycling of MPs/NPs.