Vapor-Phase Polymerization of Fibrous Pedot on Carbon Fibers Film for Fast Pseudocapacitive Energy Storage

Abstract

Poly(3,4-ethylenedioxythiophene) (PEDOT) has emerged as one of promising conductive polymers holding huge promise in pseudocapacitive energy storage. However, the conventional solution-based oxidative polymerization usually yields PEDOT electrodes with low electric conductivity and limited electroactive surface area. This work reports the preparation of highly conductive fibrous PEDOT by a vapor-phase polymerization initialized with Fe2O3 nanosheets that are uniformly electrochemically deposited on the N-doped carbon nanofibers (CNFs) film. The incorporation of highly conductive PEDOT nanofibers expands the film and simultaneously increase the film conductivity by 80 times (103 S cm−1 ). The spatially continuous and mechanically robust CNF-PEDOT film features abundant ion and electron pathways. Accordingly, an areal capacitance of 1926 mF cm −2 at PEDOT mass loading of 8.68 mg cm−2 together with a high-rate capability and high utilization efficiency of electrode have been achieved. Especially, the CNF-PEDOT film electrode exhibits an outstanding stability with 87% capacitance retention after 10000 consecutive charging and discharging cycles. Moreover, a CNF-PEDOT-based supercapacitor could deliver an energy density of 97 μWh cm−2 at power density of 0.45 mW cm−2 , surpassing the state-of-the-art PEDOT-based devices. This work will open a new avenue for preparing highly conductive PEDOT hybrid electrodes towards high-performance supercapacitors.

Keywords: Fibrous PEDOT, vapor-phase polymerization, Fe2O3 nanosheets, carbon fibers film, supercapacitor