Self-Healable Zwitterionic Ionogel via Ion Interaction and Dynamic Boronic Ester Networks

Wearable ionic electrodes have attracted significant attention as key materials for next-generation wearable sensors due to their high ionic conductivity and excellent mechanical flexibility. However, conventional ionogels often suffer from structural degradation under repeated mechanical deformation and ion leakage, limiting their long-term operational stability.

To address these challenges, we designed a PFAS-free ionogel based on sulfobetaine methacrylate (SBMA)-derived zwitterionic polymers and phenyl boronic acid. Intermolecular interactions between zwitterionic moieties improve the mechanical robustness and durability of the ionogel. Simultaneously, the zwitterionic architecture induces spontaneous ionic domain separation within the polymer network, forming continuous ionic channels that enable rapid ion redistribution and enhanced charge transport.

In addition, dynamic covalent bonds formed between phenyl boronic acid and diol groups enable reversible network reconfiguration, providing self-healing capability after damage. Furthermore, the Lewis acidic nature of boronic acid enables interactions with anions, whereas the relatively less constrained cations remain mobile and readily redistribute under external mechanical stimuli. This ion mobility difference induces localized charge separation and promotes charge polarization within the electrode. Consequently, mechanically induced ion redistribution generates amplified polarization changes, resulting in enhanced electrical sensitivity and signal output.

Consequently, the proposed zwitterion-based self-healable ionogel achieves enhanced durability through strong intermolecular interactions, self-healing and leakage resistance through a dynamic boronic network, and stable ion transport with charge polarization. Therefore, this material represents a promising PFAS-free platform for next-generation luminescent electrodes and wearable sensors requiring high sensitivity and long-term operational stability.