Dynamic assembly of electrically conductive PEDOT:PSS nanofibers in electrospinning process studied by high speed video

• Commercial PEDOT:PSS was electrospun into highly conductive submicron fiber mat.
• Single PEDOT fiber conductivity reached 35.5 S/cm on par with bulk conductivity.
• Dynamic assembly phenomenon in electrospinning of conductive fiber was observed.
• Governing parameters of fiber diameter for conductive PEDOT were examined.

Electrospinning process is used to generate micrometer to nanometer sized fibers to form nonwoven mats, which is of great interest to produce functional materials exhibiting very high surface area needed to boost efficiency of devices such as sensors, catalyst carriers and drug delivery.Intrinsic conductive polymer materials, like PEDOT:PSS, offer unique material design pathways for a range of emerging flexible electronics applications, including flexible transparent electrodes, LEDs and photovoltaics. In these applications, conductivity and interfacial area of the intrinsic conductive polymer strongly affect the efficiency of the final assembled device. High conductivity increases the efficiency of the device by reducing the resistance. Large interfacial area provides more location for electron hole generation or recombination. This study provides a simple and easy way to generate highly conductive nonwoven nanomat of commercially available intrinsic conductive polymers. Spinnability and conductivity are achieved by using a very small amount of very high molecular weight PEO that provides stability in electrospinning process without interfering the percolation path of PEDOT:PSS within nanofibers. High speed video observations revealed a unique spinning pattern of fiber standing at the collecting plate in electrospinning. This was solved by introducing an air stream flowing along the direction deposition. Effect of humidity, viscosity and electrospinning voltage on electrospun fiber diameters was also investigated.