Longevous ionogels with high strength, conductivity, adhesion and thermoplasticity

Abstract

The longevity of flexible electronics substantially influences their viability for practical use. At present, the service life of pliable devices utilizing conductive gels is frequently compromised due to factors inclusive but not limited to solvent loss. Taking cues from the steadfast structure of human tissues, we hereby delineate a solvent-assisted strategy to fabricate ionogels, predicated on a supramolecular network of hydrogen bonds. Upon subjecting these ionogels to realistic operational environments, it has been empirically ascertained that they maintain a steadfast mechanical and electrical consistency for a minimum duration of 22 months. In terms of dynamic stretchability, they effortlessly endure one million stretch cycles, even when faced with a notch. The induction of a supramolecular structure within the ionogel not only confers exceptional mechanical attributes but also simultaneously enhances conductivity, a feat paralleled by few recent explorations. Furthermore, these ionogels boast of superior anti-freezing and adhesive characteristics, including a toughness extending up to 17.96 MJ/m3 at an ultra-low temperature of −50 °C, and an adhesive capacity permitting movement and bearing of items weighing over 10,000 times its own weight, the lap-shear strength can reach 30.2 kPa. Intriguingly, these gels demonstrate thermoplastic behavior, which facilitates their easy reshaping into diverse forms. Such compelling attributes amplify the potential of supramolecular ionogels, positioning them as formidable contenders for flexible electronics in stringent and challenging scenarios.