A highly adhesive, self-healing and perdurable PEDOT:PSS/PAA–Fe3+ gel enabled by multiple non-covalent interactions for multi-functional wearable electronics

Abstract

High adhesion, flexibility, and performance stability are of great importance for wearable electronics. Extensive efforts have been devoted to developing conductive poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) composites, including their design and modification, in this regard because of their good dispersion in water. However, further applications are hindered by their inherently poor stretchability (<10%) and poor stability. Thus, a robust PEDOT:PSS/poly(acrylic acid) (PAA)–Fe³⁺ gel with good mechanical properties, adhesion, and favorable self-healing performance was successfully prepared in this work. PSS performed as an active template, and a small amount of PAA with deformable straight chains was introduced and anchored through ionic cross-linking. In particular, the composite hydrogel was treated with ethylene glycol (EG) to transform it into an organic gel, which exhibited outstanding environmental adaptability, including undergoing prolonged exposure without aging and showing stable performance even at low temperature. Meanwhile, maintaining the excellent electromechanical signal transmission capabilities of PEDOT, this material demonstrated high potential for application in wearable electronics.