Recent Advances in the Photoreforming of Plastic Waste: Principles, Challenges, and Perspectives

Photoreforming (PR) technology is a green and sustainable approach to tackling the environmental pollution problems generated by plastic waste. In this review, recent advances in the PR of plastic waste are summarized that include the design of photocatalysts, regulations on the products, and innovations on the PR devices and compared to traditional methods. The scientific principles of PR reactions in thermodynamics and kinetics are discussed, and approaches to improve the efficiency of PR reactions are proposed, that involve enhancement in light absorption ability, charge carrier migration/separation efficiency, and surface reaction rate. Particularly, the enhancement for H2 production in the PR reaction is highlighted, and the applications using large-scale reactors are discussed, with advantages and disadvantages of recent reactor configurations. In conclusion, the perspectives on the applications of PR in plastic degradation and hydrogen evolution are given. This review thus comprehensively summarizes scientific principles, challenges, and perspectives of PR reactions on plastic waste to improve the overall efficiency and potential to be applied in the industry.