Facile Fabrication of Hierarchically Porous Graphene/poly(1,5-Diaminoanthraquinone) Nanocomposite Fibers As Flexible and Robust Free-Standing Electrodes for Solid-State Supercapacitors

Background: Fiber-shaped supercapacitors have attracted more and more interests for portable/wearable electronics. However, the practical application is suffering from their tedious fabrication and limited electrochemical performance. Methods: Here, hierarchically porous graphene/poly(1,5-diaminoanthraquinone) nanocomposite (ErGO/ PDAA) fibers were fabricated as flexible and robust free-standing electrodes for supercapacitors, via facile coagulation of expanded graphene oxide (EGO) and PDAA nanomaterials with different morphologies, such as nanoparticles (PNPs), nanotubes (PNTs), and nanoribbons (PNRs), in CaCl2 bath, followed by reduction with hydroiodic acid (HI). Significant findings: All the three ErGO/PDAA fibers showed distinctly enhanced electrochemical property than the ErGO fiber. Furthermore, with the same feeding ratio of EGO and PDAA (6:4), the ErGO/PNTs fiber possessed better electrochemical capacitive property than the other two, ErGO/PNPs and ErGO/PNRs fibers, owing to the unique hierarchical pores. The solid-state symmetric supercapacitor (SSC) possessed specific capacitance, energy and power densities of 35.0 mF cm-1, 3.11 mWh cm-1, and 61.4 mW cm-1, respectively, and retained 83.3% of its initial capacitance after 5000 cycles. (c) 2021 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.