Solar-Driven Plastic Upcycling Coupled with Valuable Reduction Reactions

Abstract

Solar-powered valorization of plastic waste has emerged as a promising strategy to address the dual challenges of environmental pollution and sustainable carbon resource utilization. By harnessing solar energy and enabling spatially separated redox reactions, solar-driven systems facilitate integrated upcycling pathways that couple oxidative upcycling of plastic with value-added reductive transformations, which overcome the thermodynamic constraints of conventional single transformation, enhance the charge carrier utilization, and economic benefits. This review highlights recent advances in solar-driven photocatalytic and photoelectrocatalytic plastic upcycling integrated with valuable reduction reactions, with a focus on charge transfer properties at substrate-catalyst interfaces, and structure-property relationships. The photooxidative conversion of different plastic wastes is first discussed (such as polyethylene terephthalate, polyolefins, polystyrene, polyvinyl chloride, and polylactic acid) into valuable chemical products. Then, the progress of solar-driven plastic waste-assisted H₂ evolution, CO₂ reduction, and H₂O₂ synthesis is summarized. Finally, the challenges and the perspectives on solar-driven plastic upcycling coupled with valuable reduction reactions are also put forward. This review aims to offer insight on the design of next-generation solar-driven platforms for a circular and sustainable plastics economy.