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Title: Thermo-osmotic ionogel enabled high-efficiency harvesting of low-grade heat
Low efficiency in recovering low-grade heat remains unresolved despite decades of attempts. In this research, we designed and fabricated a novel thermo-osmotic ionogel (TOI) composite to recover low-grade heat to generate electric power through a thermo-induced ion gradient and selective ion diffusion. The TOI composite was assembled with a crystalline ionogel (polymer-confined LiNO 3 –3H 2 O) film, ion selective membrane, and hydrogel film. With a 90 °C heat supply, the single TOI composite produced a high open-circuit voltage of 0.52 V, a differential thermal voltage of ∼26 mV K −1 , a peak power density of 0.4 W m −2 , and a ground-breaking peak energy conversion efficiency of 11.17%. Eight pieces of such a TOI composite were connected in series, demonstrating an open-circuit voltage of 3.25 volts. Such a TOI system was also demonstrated to harvest body temperature for powering a LED, opening numerous opportunities in powering wearable devices.  more » « less
Award ID(s):
1934120
PAR ID:
10293395
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry A
Volume:
9
Issue:
28
ISSN:
2050-7488
Page Range / eLocation ID:
15755 to 15765
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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