Tannic Acid Modified Epoxidized Natural Rubber Based High Performing Triboelectric Nanogenerator

Abstract Considering today's environmental concerns, the development of triboelectric nanogenerator (TENG) is gaining immense interest as a green energy harvesting technology. However, most materials leveraged in TENG construction are based on non‐renewable resources. Therefore, developing a bio‐based composite with high performance for the TENG application is extremely desirable. This study uses Tannic acid (TA), a naturally occurring polyphenolic compound, as a reactive bio‐filler in the bio‐based elastomer Epoxidized natural rubber (ENR‐50). This bio‐composite is utilized as a tribo‐positive pair for TENG construction, which resulted in a very high output voltage of 751 V (at 9 Hz) and 568 V (at 5 Hz). The maximum obtained power density recorded at 9 Hz is 37 W m ⁻² at 1 MΩ external load resistance and an average power density is 20 W m ⁻² at a load resistance of 10–100 MΩ. This excellent output performance results from the high electron‐donating ability of TA. It is many‐fold higher in terms of power density than recently reported all the bio‐composites. Density Functional Theory is leveraged to probe contact electrification process. The result correlates with surface energy, dielectric, dynamic mechanical properties, and surface morphologies (roughness). Notably that such a bio‐composite can be a promising material for next‐generation power harvesting technology.