Field emission effect in triboelectric nanogenerators.
Di Liu1,2, Yikui Gao1,3, Wenyan Qiao1,3
1Beijing Key Laboratory of Micro-Nano Energy and Sensor, Center for High-Entropy Energy and Systems, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 101400, P. R. China.
Nature Communications
|May 20, 2025
Summary
Field emission, previously unrecognized, limits the performance of triboelectric nanogenerators (TENGs). Suppressing this effect significantly boosts charge density and energy output in TENG devices.
Area of Science:
- Materials Science
- Energy Harvesting
- Nanotechnology
Background:
- Triboelectric nanogenerators (TENGs) convert mechanical energy to electricity.
- TENG performance was thought to be limited by contact electrification, air breakdown, and dielectric breakdown.
- A deeper understanding of limitations is needed to improve TENG efficiency.
Purpose of the Study:
- To identify new limitations in TENG performance.
- To investigate the role of field emission in contact electrification within TENGs.
- To enhance TENG output by managing field emission.
Main Methods:
- Investigated field emission arising from contact electrification in TENGs.
- Quantified the impact of field emission on surface charge density.
- Explored methods to suppress and regulate field emission effects.
Main Results:
- Discovered field emission as a novel limitation in TENGs, occurring before dielectric breakdown.
- Achieved ultrahigh surface charge density (2.816 mC m-2) by suppressing field emission.
- Demonstrated TENGs producing energy density over 10 J m-2 by regulating field emission.
Conclusions:
- Field emission is a critical factor limiting TENG performance.
- Controlling field emission is key to achieving ultrahigh charge density and energy output.
- Findings advance the understanding of contact electrification and TENG optimization.
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