Conductive polymer electrode materials with excellent mechanical and electrochemical properties for flexible supercapacitor

Abstract

Flexible supercapacitors can be applied in the field of wearable devices, which currently received much attention. As pseudocapacitive electrode material for flexible supercapacitors, PEDOT has been extensively investigated especially to improve the mechanical strength and flexibility of the electrode material, but most methods will disrupt its electrochemical performance. In this study, we designed and prepared a novel alveolate copolymer based on PEDOT by electrochemical polymerization, introducing a certain proportion of carbamate groups as side chains to form a cross-linked structure through hydrogen bonding. This copolymer has excellent flexibility due to intermolecular hydrogen bonding, and outstanding electrochemical performance, especially rate performance and cycling stability, because of the ion channel of copolymer which satisfy the rapid migration of ions. Flexible supercapacitor based on this copolymer electrode material still have 96.1 % capacity retention at high current densities (0.2 mA/cm2) compared to low current density (0.025 mA/cm2). The specific capacity retained 85 % of its initial capacity after 20,000 cycles, especially with almost no loss in capacity even after 1000 bending cycles. This alveolate copolymer with hydrogen bonding cross-linking structure provides a choice for obtaining flexible supercapacitors with excellent mechanical and electrochemical performance, which could be utilized as wearable energy storage devices.