Scalable Upcycling of Industrial Waste Polytetrafluoroethylene Into Porous Carbon Nanosheets by Zeolite Particle Templates for Capacitive Energy Storage.

Abstract

Upcycling highly stable polytetrafluoroethylene (PTFE) waste into value-added carbon materials is fundamentally hindered by its complete zero-residue pyrolysis, which exclusively emits hazardous fluorocarbons rather than forming solid carbon frameworks. Herein, we present a scalable zeolite-particle-templated cocarbonization strategy that catalytically transforms industrial PTFE waste into hierarchical porous carbon nanosheets (PCNs) while fixing over 81% of the fluorine as recyclable NaF. Comprehensive mechanistic investigations reveal that the ZSM-5 template electronically activates C─F bonds and lowers the defluorination barrier, driving a successive-condensation structural evolution. The resulting PCN, featuring an ultrahigh specific surface area and hierarchical porosity, delivers exceptional dual-mode energy storage performances. In supercapacitors, PCNs achieve a remarkable specific capacitance of 429.6 F g^-1 and outstanding rate capabilities driven by reversible pseudocapacitance and ion coadsorption. Concurrently, in carbon-based aqueous zinc-ion batteries (CAZBs), the PCNs deliver a high specific capacity of 267.0 mAh g^-1 with robust extreme-temperature adaptability (-25°C). Validated by a continuous industrial-scale piping and instrumentation design (PID), this strategy demonstrates high commercial viability with low energy storage costs, pioneering a waste-to-wealth strategy for advanced carbon materials for energy storage.