Integrating all-yarn-based triboelectric nanogenerator/supercapacitor for energy harvesting, storage and sensing

Abstract

In the burgeoning field of energy harvesting, the integration and miniaturization of triboelectric nanogenerators with supercapacitors (TENG-SC) offers a promising frontier for developing self-powered wearable and portable sensing electronics. However, many TENG-SC systems encounter challenges in meeting wearability, high energy density, and ease of use requirements due to their complex configurations and limited flexibility. Herein, an asymmetric supercapacitor (ASC) was created by rolling up a lamellar multilayer film into a cylindrical yarn-based structure. The lamellar multilayer film comprises energy storage films with sequentially stacked layers of the positive AgNW/MnO2-TPU layer, PP separator layer, and negative AgNW/AC-TPU layer, tightly bonded to create a sandwich-like structure. The yarn-based ASC, functioning as an energy storage unit, demonstrates a high volumetric energy density of 3.2 mWh cm−3 and excellent cyclic stability (10000 cycles). Subsequently, a thinner sheath-core TPU/CB@AgNW/PMMA yarn was produced by combining wet spinning with electrospinning, which was helically wound around the yarn-based ASC to form an all-yarn-based TENG-ASC pressure-sensitive sensor that integrates energy harvesting, storage, and sensing. The miniaturized TENG-ASC yarn can convert various forms of bio-motion energy into electrical signals, with a maximum output voltage of around 3.5 V and a peak power density of 2.14 mW m−2. Simultaneously, this all-yarn-based TENG-ASC device achieves superior sensitivity (30.3 kPa−1) and has a wide pressure detection range of up to 50 kPa. This integrated system can continuously power electronic devices embedded in smart textiles, thereby extending their operational life and functionality.