Performance of triboelectric nanogenerators for harvesting mechanical energy from the ambient environment has been limited by structural complexity, cost‐effectiveness, and mechanical weakness of materials. Herein, a cost‐effective vertical contact separation mode triboelectric nanogenerator using polyethylene (PE) and polycarbonate (PC) in a regular digital versatile disc is reported. This cost‐effective nanogenerator with simplified structures is able to generate an open‐circuit voltage of 215.3 V and short‐circuit current of 80 μA. The effects of the distance of impact and the air gap between the triboelectric layers have also been tested from 3 to 9 cm, and 0.25 to 1 cm, respectively. It is determined that 0.5 cm is the optimal air gap. The nanogenerator is also tested in different real‐life scenarios including stresses produced by a moving car, walking, and a rolling skateboard over the nanogenerator. The surfaces of the triboelectric layers are further modified by surface‐charge engineering which induced a 460% increase in the output power. These tests reveal a significant electrical response and mechanical stability under stress. In summary, this study demonstrates that the relatively inexpensive PE and PC triboelectric pair has the potential to be used for highly efficient, mechanically robust triboelectric nanogenerators.
Modeling contact electrification in triboelectric impact oscillators as energy harvesters
Triboelectric energy harvesters or nanogenerators exploit both contact electri cation and electrostatic induction to scavenge excess energy from random motions of mechanical structures. This study focuses on the modeling of triboelectric energy harvesters in the con guration of contact-separation impact oscillators. While mechanical and electrostatic elements in such systems can be satisfactorily modeled based on existing theories, the underlying
physics of contact electri cation is still under debate. The aim of this work is to introduce the surface charge density of dielectric layers as a variable into the macroscopic equations of motion of triboelectric impact oscillators
by experimentally investigating the relation between the impact force and the charge transfer during contact electri cation. Specifi cally, specimens with selected pairs of materials are put under a solenoid-driven pressing
tester which charges the specimens with a vertical force whose magnitude, frequency and duty cycle can be controlled. An electrometer is used to monitor the short circuit charge flow between the electrodes from which the charge accumulation on dielectric layers can be extracted. With results from parameter-sweep tests, the produced map from contact force to surface charge density can be integrated into equations of motion via curve fitting or interpolation.
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- Award ID(s):
- 1662925
- NSF-PAR ID:
- 10109330
- Date Published:
- Journal Name:
- Modeling contact electrification in turboelectric impact oscillators as energy harvesters
- Volume:
- 10970
- Page Range / eLocation ID:
- 32
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1117/12.2513949
