Anion-Selective Ion Conductor Boosting Highly Flexible All-In-One Electrochromic Fabrics

Abstract

Flexible all-in-one electrochromic fabrics (AECF) have attracted attention for application in wearable intelligent electronics. However, undifferentiated and disordered ion transport within the AECFs usually cause a slow transfer kinetics of reactive ions and thus restrict their electrochromic performance. Here, a new strategy is proposed to optimize active ion transport based on a well-designed anion-selective ion conductor (ASIC) for boosting the anionic AECF. The ASIC is developed by the interaction difference between ions and electronegative functional groups in the fabric substrate. Benefiting from cation immobilization and free anion transport, the ASIC exhibits both high anion transference number (0.75) and ionic conductivity (2.41 × 10⁻³ S cm⁻¹) at room temperature. Such optimization of anion transport dynamics enhances the efficiency of the electrochromic redox reaction in the polyaniline-based anionic AECF, contributing to a significant improvement of the overall electrochromic performance. Based on the switchable earth yellow and dark green discoloration, the AECF is further integrated into a camouflage uniform, achieving dynamic environment adaptation in deserts or forests. This work is anticipated to provide some fresh ideas for developing functional ion conductors of electrochromic fabrics toward applications in wearable intelligent electronics.