Self-healable, stretchable triboelectric nanogenerators based on flexible polyimide for energy harvesting and self-powered sensors

Self-healing triboelectric nanogenerators (TENGs) are new, stable and durable energy harvesters. Polyimide (PI) is a promising negatively charged material that has been widely developed as a negative friction material for TENGs, but self-healing PI-based TENGs are currently vacant. Here, we reported a self-healing TENG device fabricated by self-healing PI for energy harvesting and motion sensing. The designed and fabricated PI-based TENGs exhibited excellent intrinsic self-healing and shape tailorability properties. The self-healing properties are derived from the dynamic disulfide bond exchange and flexible PDMS fragments in the PI backbone, which can recover its damage and output performance at 100 °C for 3 h. The output performance of the fabricated 6FDA-4PDA-PDMS-PI-based TENG was double that of the normal PI-based TENG due to CF3 electron-absorbing groups and siloxane fragments in the PI backbone. Finally, the applications of self-healing PI-based TENGs to harvest energy to drive commercial electronic devices and joint motion sensing were demonstrated. This work provides theoretical guidance for the fabrication of self-healing TENGs with reliable output performance and practical applications, contributing to the future of sustainable energy and wearable electronics.