Strong, Antifatigue, and Ionically Conductive Organogels for High-Performance Strain Sensors

Abstract

Conductive organohydrogels with flexibility and biocompatibility have attracted extensive attention in bioelectronic devices. However, poor mechanical properties and crack propagation resistance have severely limited their applications. Herein, strong, tough, and ionically conductive organogels (ICOs) with outstanding fatigue resistance are prepared based on simultaneous construction of dense cross-linked polymer network with numerous crystalline domains and ionically conductive network during the solvent exchange. ICOs show excellent mechanical properties with tensile strength and elongation at break as high as 16.7 ± 0.9 MPa and 1112.4 ± 120.3%, respectively. Moreover, the fracture energy and fatigue threshold can reach 34.0 ± 4.7 KJ/m 2 and 561.3 ± 59.6 J/m 2 , respectively, exhibiting outstanding crack resistant properties. ICOs with antifreezing performance are used for strain sensing with a linear working strain up to 80% and superior cycling stability, and the ICO strain sensor can monitor various body motions. The mechanically strong and antifatigue organogels show promising applications in flexible and smart electronics even in extreme environments.

Highly Stretchable, Conductive, Adhesive, and Self-Powered Ionogel Sensor for Human Motion Detection, Signal Transmission, and Traffic Monitoring

“…Flexible TENGs using hydrogels or organogels as electrodes have been investigated and reported. − Hydrogels or organogels were synthesized by immobilizing water or organic solvents in a polymer network, which have good flexibility and transparency, allowing for both flexibility and conductivity through the addition of free ions in the solvent. However, these devices are poorly environmentally stable because their ionic conductivity and flexibility decrease over time due to solvent evaporation. , In addition, these devices are susceptible to damage under high pressure because hydrogels and organogels are very soft and have poor compressive properties. For electrodes without adhesion, TENG also requires additional means of adhesion or curing to stabilize the structure, which greatly affects the efficiency of device preparation and use .…”