Dip Coating of Water-Resistant PEDOT:PSS Films based on Physical Crosslinking

Water-resistant poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films are valuable in biomedical applications; however, they typically require crosslinkers to stabilize the films, which can introduce undesired aggregation or phase separation reactions. Herein, a dipping-based process to prepare PEDOT:PSS films on nonplanar surfaces without crosslinker is developed. Sequential soaking of a dip-coated PEDOT:PSS film in ethanol and water imparts water resistance to the film. Microscopic and spectroscopic techniques are used to monitor the process and confirm that the ethanol soaking elutes the excess PSS from the film bulk, which stabilizes the film prior to the water-soaking process. The obtained films act as conductors and semiconductors on curved surfaces, including 3D-printed objects. A film deposited on a curved surface is successfully applied as the channel layer in a neuromorphic organic electrochemical transistor. This approach can enable integrated bioelectronic and neuromorphic applications that can be readily deployed for facile prototyping. A dipping-based process to prepare water-resistant poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films on nonplanar surfaces is developed. Sequential soaking of a dip-coated PEDOT:PSS film in ethanol and water imparts water resistance to the film. The obtained films serve as conductors and channel layers of organic electrochemical transistors. This technique can contribute cutting-edge technology in the additive manufacturing of conductive polymers.image

Automated summary

A dipping-based process to prepare water-resistant PEDOT:PSS films on nonplanar surfaces is developed, without the need for crosslinkers. The films gain water resistance through sequential soaking in ethanol and water. These films serve as conductors and channel layers in organic electrochemical transistors.