Stretchable ionogels: Recent advances in design, toughening mechanisms, material properties and wearable devices applications

Based on the fact that flexible electronic devices have the property of sensing human movement and monitoring physiological signals, this will pave the way for the development of wearable electronic devices that can be stretched. Ionogels have become a focal point in the field of flexible and stretchable wearable electronics by combining carefully selected chemical properties of ionic liquids with superior physicochemical properties. To accommodate with the application environment of flexible electronics, researchers' interest in toughening ionogels continues to increase. Consequently, this review systematically discusses the advancements made in stretchable ionogels from both structural design and toughening mechanism perspectives. Moreover, this review classifies these ionogels for flexible stretchable wearable electronic devices into several key application areas, including ionic skin, human motion detection, human–machine interactions and flexible energy storage devices. Finally, the challenges and prospects of stretchable ionogels are summarized, providing forward-looking strategies for further applications in wearable electronics. This review aims to emphasize the benefits of stretchable ionogels for wearable electronic devices and to provide feasible solutions for designing efficient wearable electronic devices.