Molecular Mechanism Underpinning Stable Mechanical Performance and Enhanced Conductivity of Air-Aged Ionic Conductive Elastomers

Abstract

Ionic conductive elastomers (ICEs), thanks to their liquid-free nature, have emerged as one of the most promising candidates for conductors in soft ionotronics. Notably, most ionotronic devices need to work in ambient environments where the presence of water molecules is ubiquitous. Thus far, the long-term impact of ambient water on the performances of ICEs remains virtually unexplored. Here, we show that air-aged ICEs absorb a very low amount of environmental water (∼0.3–0.6 wt % of the ICEs), which endows ICEs with stable mechanical performance and strongly boosted conductivity. We study the underlying molecular mechanism and clarify that the scission of lithium bonds between lithium ions and elastomer chains provoked by diffusing water molecules accounts for the observed changes in ICE properties. This work provides guidance for the practical mass application of ICE-based soft ionotronics in ambient environments.