Free-standing and highly conductive PEDOT nanowire films for high-performance all-solid-state supercapacitors

Abstract

Recently, flexible and portable supercapacitors (SCs) have attracted increasing interest. PEDOT is a promising electrode material due to its high electrical conductivity, excellent environmental stability and cycling stability; however, the electrochemical performance of free-standing PEDOT films has not been reported yet. Herein, a simple and low-cost modified self-assembled micellar soft-template method followed by vacuum-assisted filtration has been developed to synthesize flexible and free-standing PEDOT nanowire (NW) films with very high electrical conductivity (∼1340 S cm⁻¹). The PEDOT NW film electrode with excellent flexibility exhibits excellent electrochemical performance (specific capacitance of 667.5 mF cm⁻² at 1 mA cm⁻² and good cycling stability). A flexible solid-state PEDOT NW film-based SC shows high specific capacitances of 413.5 mF cm⁻² at 1 mA cm⁻² and 306.0 mF cm⁻² at 50 mA cm⁻², an outstanding energy density of 48.3 μWh cm⁻² at a power density of 0.22 mW cm⁻² and a superior power density of 16.77 mW cm⁻² at an energy density of 19.1 μWh cm⁻². The desirable combination of excellent flexibility, high electrical conductivity, excellent electrochemical properties, and facile process scalability makes the PEDOT NW film particularly promising for portable and flexible electronics.