Spontaneous self-healing ionogels for efficient and reliable carbon dioxide separation

Abstract

Ionogels, composed of ionic liquids loaded in polymeric or inorganic networks, demonstrate great potential in CO₂ separation. However, currently utilized ionogels suffer from weak mechanical strength, damage vulnerability, and limited service life. Herein, we report spontaneous self-healing ionogels with imine bond cross-linked supramolecular polymer networks for CO₂ separation. The reversibility and high bond energy of the imine bonds endow the resulting ionogels with high mechanical strength, good resilience, wide operating temperature range and room temperature spontaneous self-healing capability. The ionogels developed in this study exhibit excellent gas separation performance owing to the good CO₂ solubility in the ionogel components. These properties allow ionogels to be used as CO₂ separation membranes capable of spontaneously and repetitively healing the damage (e.g. fracture and a 0.045 mm² through hole) in 48 h with a completely restored CO₂ separation performance, significantly improving the service life and reliability. These findings provide a promising strategy to synthesize spontaneous self-healing ionogels with high mechanical strength and excellent gas separation performance and demonstrate their great application potential in CO₂ separation processes.