In situ CO2 capture: a general strategy for valorizing waste polycarbonate into high-value chemicals.

Efficiently utilizing carbon resources from waste plastics and expanding pathways for high-value chemical production are crucial for sustainable development and advancing the circular economy. However, the challenge of inert and hard-to-reuse CO2 released during plastic management remains a significant hurdle, resulting in the loss of valuable carbon resources. Herein, we propose a versatile in situ CO2-capturing strategy for the efficient upcycling of polycarbonate (PC) to produce bisphenol A (BPA) and diverse CO2-upgraded products. Utilizing a variety of CO2-capturing reagents, including nitriles, epoxies, amines, alkynes and alcohols, we achieve complete depolymerization of PC under mild, atmospheric conditions and efficiently co-produce value-added chemicals such as nitrogen-containing heterocycles, cyclic carbonates and acetylenic carboxylic acids. Mechanistic studies reveal that the process involves a more thermodynamically favorable in situ CO2 capture pathway compared to conventional gaseous CO2. This strategy offers a new route to unlock carbon resources from carbonate-based polymers for diversified chemical production and sustainable waste management.