Non-lithographic fabrication of PEDOT nano-wires between fixed Au electrodes

Poly(3,4-ethylenedioxythiophene) (PEDOT) nano-wires have been electrochemically grown between fixed Au electrodes on an insulating SiO2 substrate. The local DC electric field between the electrodes was used to control the diffusion of the 3,4-ethylenedioxythiophene (EDOT) monomer which was then polymerised in situ by the same applied field to create a stable, insoluble wire of width 500–700 nm. Relatively smooth and conducting nano-wires (∼10 S cm−1) resulted from the application of step-wise decreasing DC voltages. The PEDOT wire was characterised using Raman spectroscopy and atomic force microscopy (AFM). Current-voltage measurements indicate Ohmic and space-charge limited conduction, depending on applied bias, for Au electrodes.