Autonomously Self‐healing, Adhesive, and Stretchable Triboelectric Nanogenerator Using Multifunctional Hydrogel‐Elastomer Double Layer with a Power Management Circuit

Abstract Triboelectric nanogenerators (TENGs) are promising candidates replacing conventional batteries in wearable devices, owing to their self‐powering properties. Although TENGs can convert mechanical energy into electrical energy, excessive mechanical stresses can degrade their performance. Moreover, conformal adhesion to skin is required to improve its performance in wearable devices. Here, a stretchable, adhesive, and self‐healing single‐electrode TENG with a multifunctional hydrogel‐elastomer double layer is developed. Carbon nanotubes (CNTs)‐doped hydrogel is used as the electrode. Subsequently, the electrode is covered with an Ecoflex elastomer that acted as a triboelectrification layer. The soft tissue‐like properties of the hydrogel allow conformal adhesion to nonplanar skin, whereas the dynamic polymer network of the hydrogel endows toughness and ability to self‐heal (within 5 min) against external damage. The TENG demonstrates an output voltage and current peak at 180 V and 0.8 µA. Moreover, it can generate a maximum power peak at 37.8 mW m −2 , which is sufficient to power small electronics like stopwatches and light‐emitting diodes, with a power management circuit. The proposed TENG devices can function as telecommunication touch panels via Morse code. Thus, this study presents a promising approach for advancing the flexible power supplies and self‐powered sensors that can be applied to wearable devices.