Beyond mechanical recycling: artificial photosynthesis enables polyester plastics upcycling into valuable chemicals

Abstract The accumulation of plastic waste presents a severe environmental challenge. Among these materials, polyester plastics are particularly promising for chemical recycling into valuable products due to their ester-rich backbones and controllable crystallinity, though the process remains technically challenging. Artificial photosynthesis has recently emerged as a promising approach, owing to its ability to convert waste into wealth through partial oxidation of plastic substrate under mild conditions. In this review, we elaborate on various pathways of polyester plastics conversion, such as polyester plastics upcycling integrated with water splitting, polyester valorization coupled with CO2 reduction, and organonitrogen synthesis from polyester. This review begins by discussing the fundamental mechanisms of photoinduced plastic conversion and its advantages compared with traditional plastic disposal and biological treatment approaches. Subsequently, the design principles for engineering high-performance photocatalysts, such as tuning redox potentials, promoting charge separation, enhancing substrate absorption, and leveraging photothermal-assisted photocatalysis, were outlined to provide guidance for the selection and modification of photocatalysts. Furthermore, recent advances in plastic conversion and the underlying mechanisms have been reviewed. Besides, techno-economic assessment and environmental impact have been raised to evaluate and advance photodriven plastic valorization. Finally, the future challenges and research perspectives, such as reactor design and the synthesis of long-chain compounds, are critically discussed. This review presents a blueprint for the development of advanced photocatalysts for polyester plastic conversion, thereby closing the carbon loop for post-consumer polyester plastics.