Cellulose‐Based Fully Green Triboelectric Nanogenerators with Output Power Density of 300 W m⁻²

Abstract Triboelectric nanogenerators (TENGs) have attracted increasing attention because of their excellent energy conversion efficiency, the diverse choice of materials, and their broad applications in energy harvesting devices and self‐powered sensors. New materials have been explored, including green materials, but their performances have not yet reached the level of that for fluoropolymers. Here, a high‐performance, fully green TENG (FG‐TENG) using cellulose‐based tribolayers is reported. It is shown that the FG‐TENG has an output power density of above 300 W m −2 , which is a new record for green‐material‐based TENGs. The high performance of the FG‐TENG is due to the high positive charge density of the regenerated cellulose. The FG‐TENG is stable after more than 30 000 cycles of operations in humidity of 30%–84%. This work demonstrates that high‐performance TENGs can be made using natural green materials for a broad range of applications.