Capacitors based on PEDOT nanowire electrodeposits

Abstract

The capacitive properties of poly(3,4-ethylenedioxythiophene) nanowires (PEDOT-nw) obtained in situ by the electrosynthesis of EDOT in acetonitrile by cyclic voltammetry on a transparent ITO electrode that has been previously modified with a thin layer of PEDOT, on which mesoporous SiO2 is deposited. Silica acts as a template for the generation of polymer nanowires. The voltammetric profiles are consistent with a large increase in the surface area of the electrode, while their Raman spectroscopy and SEM microscopy demonstrate the formation of polymer nanostructures on the electrode surface. Also, by SEM, the presence of PEDOT deposit is verified in the form of nanowires 30 nm in diameter. On the other hand, galvanostatic measurements show a 20 times higher specific capacity for PEDOT-nw (516.12 Fg(-1)) compared to PEDOT bulk (19.62 Fg(-1)). In the case of PEDOT-nw, it is also worth noting a 92.3% retention capacity after 1000 successive charge/discharge cycles. Thus, it is verified that PEDOT-nw modified electrodes are an excellent candidate to be used in polymer-based capacitors.