Nature-inspired power generation: cellulose-centric triboelectric nanogenerators for next-generation electronics

Abstract

Cellulose has evolved as a pivotal triboelectric layer, driving the development of sustainable triboelectric nanogenerators (TENGs) for enhanced sensor performance and improved energy harvesting systems. Alongside its wide availability and natural degradability, it exhibits a triboelectric nature due to the abundance of hydroxyl groups, an interfacial charge-transfer mechanism, polarity, and a hierarchical structure. This review article provides a mechanistic insight and an engineering-centered perspective on cellulose-based TENGs, integrating the principles and charge-transfer models, as well as the factors affecting triboelectric output. Different forms of cellulose are rigorously assessed, indicating that their type, surface electronic chemistry, and dielectric properties alter the performance and stability of TENGs. Advanced functionalization techniques, which include chemical modification, addition of dopants as well as 2D and conductive fillers, and micro- and nano-structuring, are emphasized for their contributions to improving the triboelectric properties, output, and environmental stability. Furthermore, multiscale characterization techniques integrate electrostatic mapping, microscopy, spectroscopy, and operational-level analysis to establish a structure–characteristic–output relationship. Additionally, this review focuses on next-generation AI-ML facilitated models for improved material optimization and device fabrication, along with a life-cycle assessment method that alleviates concerns regarding scalability, durability, and post-use sustainability. Overall, cellulose has shown applications in wearable devices, biomedical fields, self-powered sensors, and as an energy harvester, making it a potential material for intelligent and next-generation triboelectric devices.