Abstract Poly (3,4‐ethylene dioxythiophene) (PEDOT) is an electrically conductive polymer that shows various promising applications in flexible electronics. However, previous studies have mostly focused on enhancing the conductivity, while ignoring the design and development of porous PEDOT materials. Herein, we report a novel and sustainable strategy of utilizing a deep eutectic solvent of ferric chloride hexahydrate/acetamide to guide the interface‐controlled polymerization of PEDOT at room temperature. The obtained PEDOT material has its unique features of high porosity of 70.61%, high specific surface area of >58 m2/g, and ideal electrical conductivity of 6500 S/m, resulting in a wide voltage window of up to 1.2 V. Notably, this porous PEDOT can be easily formulated into printable electronic ink with controllable rheological properties, process ability, and recyclability, exhibiting the outstanding energy storage behavior in wearable electronics. This study reports an effective, green approach for the development of porous PEDOT materials and printable flexible devices.
