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Abstract Harvesting body heat using thermoelectricity provides a promising path to realizing self-powered, wearable electronics that can achieve continuous, long-term, uninterrupted health monitoring. This paper reports a flexible thermoelectric generator (TEG) that provides efficient conversion of body heat to electrical energy. The device relies on a low thermal conductivity aerogel–silicone composite that secures and thermally isolates the individual semiconductor elements that are connected in series using stretchable eutectic gallium-indium (EGaIn) liquid metal interconnects. The composite consists of aerogel particulates mixed into polydimethylsiloxane (PDMS) providing as much as 50% reduction in the thermal conductivity of the silicone elastomer. Worn on the wrist, the flexible TEGs present output power density figures approaching 35 μWcm−2at an air velocity of 1.2 ms−1, equivalent to walking speed. The results suggest that these flexible TEGs can serve as the main energy source for low-power wearable electronics.
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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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