Preparation And Properties Of The PEDOT/PSS Free-standing Thin Films

Conductive organic polymers have attracted great interest owing to their many potential future applications for fabrication of low cost,flexible,and printable electronic devices.Among conductive polymers,poly(3,4-ethylenedioxythiophene):polystyrene sulfonate(PEDOT/PSS)is very attractive because of its high conductivity,high work function,chemical stability,transparency to visible light,and wet-processing.Three important wet-processing methods have been developed to prepare the PEDOT/PSS film: drop coating,spin coating and bar-coating.Most of the films are standing PEDOT/PSS films.However,there were few reports on free-standing PEDOT/PSS thin films.In this thesis,we have systematically investigated preparation and properties of free-standing PEDOT/PSS thin films.Firstly,PEDOT/PSS film was prepared on PET substrate by bar-coating method.The PEDOT/PSS film has 300 nm in thick,410 S/cm in conductivity and 76% in transmittance of 550 nm wavelength.Then,the standing film was separated from the PET substrate in water and transferred to the non-woven fabric,and drying.Subsquently PEDOT/PSS free-standing thin film was successfully prepared and characterized.The PEDOT/PSS free-standing thin film has 330 nm in thick,280 S/cm in conductivity and 75% in the transmittance.The free standing thin film was relatively weak in mechanical strength.On the other hand,the PEDOT/PSS-HNTs standing thin film and free-standing thin film were prepared similarly but through mixing HNTs in PEDOT/PSS dispersions.The PEDOT/PSS-HNTs standing thin film has 920 nm in thick,72 S/cm in conductivity and 53% in the tranmittance,while the PEDOT/PSS-HNTs free standing film has 1000 nm in thick,10-100 S/cm in conductivity and 60% in the transmittance.The free standing thin film was considerably strong in mechanical strength.