Electrochemical properties of porous carbon derived from polymer waste

Abstract

The exponential accumulation of non-degradable polymer waste poses a severe environmental challenge. In order to achieve high-value recycling and meet the demand for advanced energy storage, this study converts various polymer wastes into high-performance porous carbon (PC) electrode materials for supercapacitors. The waste hollow fiber filter (HFC), polyurethane shoe material (PUC) and PET foam (PFC) were converted into PC with a customized morphological framework through pre carbonization combined with high temperature KOH chemical activation. The results showed that HFC activated with 1:4 KOH and CAR at 750 ℃ achieved 2934 m2·g-1 specific surface area (SSA) and synergistic in situ N/O self-doping. This structural optimization provides an excellent specific capacitance (SC) of 297 F·g-1 at 1A·g-1. Dynamics analysis shows that enriched Faraday redox sites and graded porosity result in an ultra-low charge transfer resistance of 0.22 Ω and a high capacitance control contribution of 84.7% at 20 mV·s-1. In addition, PUC activated at 850 ℃ exhibited a coral like rigid 3D skeleton, producing an SSA of 1467 m2·g-1, a capacity retention rate (CRR) of 85.4% at 10 a·g-1, and an internal resistance as low as 0.97 Ω. PFC (CAR 1:4) activated at 750 ℃ forms a honeycomb structure, providing 2281 m2·g-1 SSA and 296 F·g-1, with excellent electrolyte diffusion kinetics. This work elucidates the relationship between precursor topology and pore evolution, providing a sustainable approach for the next generation of energy storage devices.