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Abstract: This paper aims to develop a novel concept for energy harvesting via flexible inverted flags combining photovoltaic cells with piezoelectric flexible films. Using technology currently available, we have designed and fabricated piezo-pyro-photo-electric harvesters made of polyvinylidene fluoride (PVDF) piezoelectric elements combined with mini solar panels made of silicon. Experimental measurements of the motion dynamics and power generation were collected for the flags when subjected to wind, heat, and light sources simultaneously and individually. Results indicate a significant improvement in energy harvesting capability compared to isolated single piezoelectric devices. Thus, we anticipate a substantial impact of piezo- pyro-photo-electric energy harvesting device applications where remote power generation is needed. The Flag uses flexible piezoelectric and pyroelectric strips and flexible photovoltaic cells panel. The piezo-pyro- simultaneously generates power through movement and heat, respectively, while the photovoltaic cells harvest solar energy to produce electric power. The beauty of this Flag is to develop power day and night depending on the energy sources available. The basic concept is presented and validated by laboratory experiments with controlled airflow, light, and infrared heat. The maximum voltage generated was 60 mV when the Flag was simultaneously exposed to low-level wind, thermal and light energies.
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Flexible Hybrid Piezoelectric‐Electrostatic Device for Energy Harvesting and Sensing Applications
Abstract Converting mechanical energy from either the ambient environment or the human body motions to the useful electrical energy will revolutionize power solutions for flexible electronics. Here, a hybrid energy harvesting strategy is reported, which combines porous polymeric piezoelectric film with an electrostatic layer as an integration for converting the mechanical energy into electrical energy. The piezoelectric materials through engineered microstructures are developed to enhance energy generation due to the higher compressibility and larger surface contact area. The electrostatic effect from the charged layer further contributes to the generation of electrical charges. By directly coating the stretchable carbon nanotubes onto the elastomers, more intimate integration of the hybrid energy harvesters enables the designs for complex electronics. Such flexible hybrid piezoelectric‐electrostatic device exhibits superior energy harvesting performance with a voltage output of 1.95 V, which improves 30% and 100% compared to the electrostatic and piezoelectric alone device, respectively. Experiments are also performed to demonstrate the implementation of the hybrid device's energy conversion to power small electronics and recognition of different body motions. Such hybrid strategy provides a new solution toward future energy revolution for flexible electronics.
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- Award ID(s):
- 2106459
- PAR ID:
- 10394778
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Interfaces
- Volume:
- 10
- Issue:
- 8
- ISSN:
- 2196-7350
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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