Wearable, freezing-tolerant, and self-powered electroluminescence system for long-term cold-resistant displays

Tremendous efforts in wearable optoelectronics have recently harnessed considerable advances in intrinsically stretchable electroluminescence (EL) devices. However, developing wearable optoelectronics that maintain long-term stability in harsh cold environments is still challenging. Here, a wearable, freezing-tolerant, and self-powered EL system is developed based on organohydrogel-based EL (OH-EL) device integrated with liquid electrolyte-based single-electrode triboelectric nanogenerator (LE-TENG), in which the OH-EL device based on self-healing and highly conductive organohydrogel electrodes can be directly lit by the LE-TENG. The stretchable OH-EL device demonstrates a bright and uniform light emission under 140% tension stretching as well as severe mechanical deformations of bending, rolling, and twisting. Moreover, the optical performances of the OH-EL device exhibit excellent repeatability and durability after continuous 2000 cycles. More importantly, bright blue-green light emission of the self-powered EL system stored at 253 K can maintain for six months, demonstrating extremely long-term freezing-tolerant capability. Furthermore, while harvesting the biomechanical energy of hand slapping and knee/elbow bending, the self-powered EL system worn on different parts of human body can achieve real-time visualized displays. Consequently, the simple fabrication and unique operation of the self-powered EL system demonstrate potential application in cold-resistant displays, wearable self-powered photoelectric devices, soft robotics, and other fields.