Highly stretchable, self-healable, and environment-adaptable ionogel-based high-output triboelectric nanogenerator for self-powered wearable ionotronics

Fabricating stretchable, self-powered ionotronics with self-healing and environmentally adaptive properties is essential but remains a significant challenge. Herein, we present a strategy to address this challenge by developing physical-chemical cross-linked ionogels with dynamic imine bonds using flexible and multifunctional macromolecular cross-linkers of hyperbranched poly(ethylene imine) (PEI) in the hydrophobic ionic liquid of 1butyl-3-methylImidazolium bis(trifluoromethyl sulfonyl) imide (BMIMTFSI). The unique dynamic cross-linking networks impart the ionogel with remarkable stretchability (1170 %), strong mechanical strength (1.03 MPa), good room temperature ionic conductivity (1.41 mS/cm), wide operating temperature range (- 83-300 degrees C), excellent self-healability and reprocessability. Notably, the ionogel-based flexible triboelectric nanogenerator (TENG) demonstrates outstanding durability and good mechanical/temperature/humidity stability, along with high and consistent electrical output performance in the range of - 40-80 degrees C, achieving an output voltage of 218 V and maximum output power density of 360 mW m- 2. Furthermore, the prepared TENG can easily light up 280 light-emitting diodes (LEDs) and charge up capacitors to power commercial electronics. Importantly, the flexible TENG can serve as a self-powered wearable sensor to monitor various human motions in real-time, offering potential applications for next-generation self-powered flexible ionotronics with excellent environment adaptability and self-healing capabilities.