Highly conductive poly(3,4-ethylenedioxypyrrole) and poly(3,4-ethylenedioxythiophene) enwrapped Sb2S3 nanorods for flexible supercapacitors

Abstract

Composites of poly(3,4-ethylenedioxypyrrole) or PEDOP and poly(3,4-ethylenedioxythiophene) or PEDOT enwrapped Sb₂S₃ nanorods have been synthesized for the first time for use as supercapacitor electrodes. Hydrothermally synthesized Sb₂S₃ nanorods, several microns in length and 50−150 nm wide, offer high surface area and serve as a scaffold for coating conducting polymers, and are a viable alternative to carbon nanostructures. Fibrillar morphologies are achieved for the PEDOP–Sb₂S₃ and PEDOT–Sb₂S₃ films in contrast to the regular granular topologies attained for the neat polymers. The remarkably high nanoscale (∼5 S cm⁻¹) conductivity of the Sb₂S₃ nanorods enables facile electron transport in the composites. We constructed asymmetric supercapacitors using the neat polymer or composite and graphite as electrodes. High specific capacitances of 1008 F g⁻¹ and 830 F g⁻¹ (at 1 A g⁻¹), enhanced power densities (504 and 415 W kg⁻¹) and excellent cycling stability (88 and 85% capacitance retention at the end of 1000 cycles) are delivered by the PEDOP–Sb₂S₃ and PEDOT–Sb₂S₃ cells relative to the neat polymer cells. A demonstration of a light emitting diode illumination using a light-weight, flexible, supercapacitor fabricated with PEDOP–Sb₂S₃ and carbon-fiber cloth shows the applicability of Sb₂S₃ enwrapped conducting polymers as sustainable electrodes for ultra-thin supercapacitors.