Recent progress on nature-derived biomaterials for eco-friendly triboelectric nanogenerators

Eco-friendly triboelectric nanogenerator (eco-TENG) is considered as a next-generation renewable kinetic energy-harvesting technology, especially for its potential use as a power supply unit for self-powered electronics. For eco-TENGs, nature-derived biomaterials, which are non-toxic to human and environment, highly biocompatible, and abundant in nature, are used for tribopositive or tribonegative materials, or both. Here, recent progress in nature-derived biomaterials exploited for eco-TENGs and their energy-harvesting performances are reviewed, focusing on refined, hybridized, post-treated, or not. Since biomaterials that exist in nature have evolved over hundreds of years to hundreds of thousands of years, their diversity, novelty in physicochemical structure, and high safety to nature hold enormous potential as carbon-neutral energy materials. Furthermore, scalability and cost-effectiveness of their fabrication methods make them promising as industrially viable eco-materials.