Lightweight, elastic and conductive pure PEDOT:PSS foam for dual-mode sensing

Abstract

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is a high-performance conductive polymer that needs to be assembled into a macroscopic foam form in many fields. How to address the incompressibility and lack of fatigue resistance of the foam skeleton of PEDOT:PSS remains a huge challenge. In this study, a self-assembled bubble-enhanced layered porous PEDOT:PSS (SBLPP) foam with a multi-scale porous structure was prepared based on a simple hydrothermal self-assembly and dual template multifunctional technology without introducing other template materials and reinforcement materials. During the hydrothermal self-assembly process, the removal of insulating PSS and the conformational change of PEDOT enhanced the strength, hydrophobicity, and conductivity of the PEDOT:PSS skeleton. In addition, the stress was effectively transmitted through the bubble cavities combined with the layered porous structure, making the SBLPP foam exhibit excellent compressibility, fatigue resistance, and thermal insulation. Sensors based on SBLPP foam can effectively and independently detect changes in temperature and pressure and simultaneously convert the two stimuli into mutually non-interfering voltage and resistance signals. The synthesis of pure SBLPP foam provides a feasible method for constructing high-performance foam frameworks for organic conductive polymers.