Abstract:The extensive production and utilization of plastics globally have resulted in waste plastic pollution becoming a significant environmental concern. To advance sustainable development, it is crucial to enhance the recycling and reuse of these materials. Chemical upcycling strategies, particularly photocatalytic and electrocatalytic reforming technologies, offer promising solutions due to their low energy consumption, environmental compatibility, and capability to selectively convert waste plastics into high-value products. These technologies are viewed as essential for achieving a sustainable future for plastic waste management. However, the large-scale implementation of photocatalytic and electrocatalytic reforming still faces several challenges, including low catalytic efficiency, limited product selectivity, and complex separation and purification processes. This review provides an overview of recent advancements in the photocatalytic and electrocatalytic reforming of waste plastics, emphasizing the reaction mechanisms involved, the structure-performance relationships of catalysts, and the synergistic effects of coupled reactions. It also examines how different reforming systems influence reaction efficiency and product selectivity. Recent studies suggest that waste plastics can be directly degraded into microplastics and nanoplastics or converted into fuels such as hydrogen (H2) and carbon monoxide (CO), as well as high-value chemicals, like formate and acetate via photocatalytic reforming. Electrocatalytic reforming further enables the selective conversion of plastics into C1 and C2+ chemicals through tuning the applied voltage or incorporating additional reactions. Key evaluation metrics, including economic viability, reaction efficiency, scalability, product selectivity, product yield, developmental potential, and environmental impact, are compared. This assessment helps determine the practical applicability of these upcycling processes. Despite significant progress, challenges such as low reaction efficiency and limited selectivity persist in current photocatalytic and electrocatalytic systems. To address these issues, future research directions are proposed, focusing on achieving highly efficient catalysis under milder conditions, enhancing product selectivity in plastic reforming, and elucidating the underlying reaction mechanisms. Additionally, strategies for coupling photocatalytic and electrocatalytic technologies with CO2 reduction and biomass conversion are suggested to improve the yield of high-value products. Broadening these efforts to encompass CO2 reduction, N2 fixation, metal recovery, and organic synthesis is expected to enhance the efficient conversion and upcycling of waste plastics, thereby advancing the development of a circular chemical economy. Close-