NIR-Laser Induced Fast Self-Healing Micro-Supercapacitor Based on Aniline-Trimer Based Polyurethane

With increased demand for miniaturized wearable devices, there has been active research on wearable energy storage devices for integration into a single patch device. Among various energy storage devices, supercapacitors have appeared to be promising owing to high power density, fast charge/discharge time, and simple structure in addition to safety, compared to batteries. Considering the frequent movements of the wearers, those wearable devices including supercapacitors are required to be flexible/stretchable, leading to fabrication based on soft polymer materials. Thus, those soft devices are vulnerable to damages due to the deformations. As a result, extensive efforts on self-healing devices as well as materials have been recently made for extending the lifespan.<br/>In this study, we report on a laser-induced fast self-healing micro-supercapacitor (MSC) based on our novel synthesized aniline-trimer-based photothermal polyurethane (AT-PU). A room temperature self-healing interdigitated current collector of polyether-thioureas with triethylene glycol (TUEG3)-capped Au nanosheets, and MXene-based electrode are patterned on the AT-PU film using CO₂ laser patterned polyimide mask. By incorporating the same AT-PU into the ionic liquid ([EMIM][TFSI]) electrolyte with Li salt, laser-induced self-healing between the AT-PU film and the electrolyte can be achieved. AT-PU based electrolyte showed over 84% of self-healing efficiency in terms of ionic conductivity via 3 min NIR-laser induced self-healing. The fabricated MSC recovers the electrochemical performance after 808 nm NIR laser irradiation for 3 min on the bisected interface, exhibiting the full-device self-healing owing to the use of all self-healing component materials. This work demonstrates that the deliberate selection of self-healing materials and device architectures opens a new way of developing high performance full-device self-healing supercapacitor as a durable soft energy storage device with longevity.