Electrode structures of solid-liquid interface-based triboelectric nanogenerators and their applications

Abstract

Against the backdrop of carbon neutrality, the demand for sustainable energy keeps growing. Among numerous new energy technologies, the triboelectric nanogenerator (TENG) has garnered widespread attention in recent years due to its ability to harvest widely distributed tiny mechanical energy from the environment. With the advancement of TENG technology, solid‒liquid interface-based TENGs have not only enabled the recovery of mechanical energy from droplets but have also been utilized for self-powered sensing of liquid samples, demonstrating broad application potential. In recent years, in addition to research on triboelectric materials, the development of novel electrode structures has also been regarded as a crucial approach for enhancing the electrical output performance of solid‒liquid interface-based TENGs. In this review, we traced the developmental trajectory of electrode structures in solid‒liquid interface-based TENGs, and compiled the corresponding equivalent circuit diagrams and signal characteristics for devices featuring three representative electrode structures. Meanwhile, we summarized the representative applications of each electrode structure in energy conversion and self-powered sensing and discussed the suitable application scenarios for each electrode structure. We believe that this review guides the in-depth use of solid‒liquid interface-based TENGs in energy harvesting and self-powered sensing.

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2026 The Author(s). Droplet published by Jilin University and John Wiley & Sons Australia, Ltd.