Physical Cross-Linkage Constructed Supramolecular Conductive Hydrogel as Sustainable and Remolded Epidermal Electronics

Abstract

To balance the comprehensive requirements of toughness, mechanical strength, rapid self-healing, and high conductivity in supramolecular hydrogels toward wearable devices still remain a tough challenge. This paper presents a simple one-step method to construct supramolecular conductive hydrogels (SCHs) through multilevel electrostatic and coordination interactions between amphoteric polymers and metal ions, which are revealed by the density functional theory (DFT) and noncovalent interaction (NCI) analysis. The SCHs integrate stretchability (more than 1500% and 110 kPa), self-healing, remoldability, large strain sensor (0–500%), and long-term monitoring of motion and electrocardiogram (ECG) with decent conductivity (∼2.5 S/m). The self-healing and remolding of SCHs suffer from temperature dependence. Meanwhile, it is worth noting that the remolded SCHs (R-SCHs) retained all of the properties of the original SCHs (O-SCHs), such as conductivity, intelligent sensing, health monitoring, and so on, indicating that the SCHs constructed in physical cross-linking could achieve sustainable recycling in flexible electronics and smart soft materials.