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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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Pyroelectric Polyelectrolyte Brushes
Abstract Piezo‐ and pyroelectric materials are of interest, for example, for energy harvesting applications, for the development of tactile sensors, as well as neuromorphic computing. This study reports the observation of pyro‐ and piezoelectricity in thin surface‐attached polymer brushes containing zwitterionic and electrolytic side groups that are prepared via surface‐initiated polymerization. The pyro‐ and piezoelectric properties of the surface‐grafted polyelectrolyte brushes are found to sensitively depend on and can be tuned by variation of the counterion. The observed piezo‐ and pyroelectric properties reflect the structural complexity of polymer brushes, and are attributed to a complex interplay of the non‐uniform segment density within these films, together with a non‐uniform distribution of counterions and specific ion effects. The fabrication of thin pyroelectric films by surface‐initiated polymerization is an important addition to the existing strategies toward such materials. Surface‐initiated polymerization, in particular, allows for facile grafting of polar thin polymer films from a wide range of substrates via a straightforward two‐step protocol that obviates the need for multistep laborious synthetic procedures or thin film deposition protocols. The ability to produce polymer brushes with piezo‐ and pyroelectric properties opens up new avenues of application of these materials, for example, in energy harvesting or biosensing.
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- Award ID(s):
- 2204396
- PAR ID:
- 10485133
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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