Polyphenylene sulfide scaffold based flexible supercapacitor electrode with competitive areal capacitance and flame-retardant behavior

Abstract

Flexible supercapacitor electrode has been strongly developed as next-generation wearable energy storage electronics in the last decades. The state-of-the-art performance always requires the implantation of compelling energy-storage stuff and flexible scaffolds. However, the inflammable nature of such supercapacitors gives rise to safety issues, and it is a challenge to maintain high energy storage capability and flame-retardant behavior synergistically. Herein, we use a paper-making technique to engineer polyphenylene sulfide (PPS) ultrafine fibers and multi-walled carbon nanotubes (MWCNT), followed by the deposition of in-situ polymerization polypyrrole (PPy). This highly porous electrode exhibits a high areal capacitance of ~1650 mF cm−2 at a current density of 1 mA cm−2, and > 93% of capacitance retention after 5000 charging-discharging cycles at a current density of 20 mA cm−2. Notably, PPS/MWCNT/PPy electrode features noninflammability and zero generation of dense fume in the open flame. Also, the areal capacitance of the electrode remains more than 50% after 0.5 h annealing at 200 °C. This work delivers a new PPS scaffold-based supercapacitor electrode-manufacturing system directing at high energy-storage capability and harsh-environment adaptability.