From Fundamentals to Engineering Sustainable Triboelectric Materials: A Review of Cellulose Platforms.

Cellulose has become one of the most promising sustainable platforms for triboelectric nanogenerators (TENGs), driven by its abundance, mechanical robustness, chemical tunability, and compatibility with large-scale manufacturing. This paper provides a critical and mechanism-oriented review of how the molecular structure, surface chemistry, and composition of cellulose materials influence charge generation, retention, and dissipation during triboelectrification. We analyze the triboelectric properties of native, regenerated, and nanocellulose materials, as well as the methods developed to enhance their properties. Particular attention is given to surface functionalization strategies-such as fluorination, amination, and esterification that enhance charge density while mitigating humidity-induced losses. Moreover, the application of cellulose material-based TENGs has been reviewed extensively. By integrating fundamental insights with engineering considerations, a forward-looking roadmap is proposed for high-performance, recyclable cellulose-based systems for sustainable energy harvesting and self-powered sensing applications.