Room‐Temperature Depolymerization of Waste Polycarbonate and Polyester Enabled by an Electrochemically Generated Local Alkaline Microenvironment

ABSTRACT

Driven by massive production and inadequate end‐of‐life management, polycarbonate and polyester plastic pollution has become one of the most critical environmental crises. To address this mounting challenge, decades of research have yielded a variety of polycarbonate and polyester recycling technologies. Nevertheless, the majority of existing methods either afford low‐quality, low‐value products or depend on harsh conditions such as high temperature, high pressure, and corrosive bases or acids, severely restricting their scalability and economic feasibility for industrial‐scale implementation. Herein, we present an efficient electrochemical approach for the room‐temperature depolymerization of polycarbonate and polyester into value‐added monomers and derivatives, enabled by a cathodically in situ generated alkaline interfacial microenvironment at neutral bulk pH. This approach shows broad substrate compatibility with commercial‐grade and contaminated waste polycarbonate, polyester, and their blends, affording corresponding products in up to 99% yields, with its industrial potential demonstrated by a kilogram‐scale depolymerization reaction. Significantly, it realizes the direct recovery of high‐performance long carbon fibers from reinforced composites without fiber‐damaging pulverization, creating a viable upcycling route. Mechanistic studies confirm that water electroreduction generates surface hydroxyl species that act as proton shuttles, driving methanol deprotonation to form depolymerization‐active species and establishing the indispensable alkaline microenvironment.