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Title: Solution-printable fullerene/TiS 2 organic/inorganic hybrids for high-performance flexible n-type thermoelectrics
Solution-printable and flexible thermoelectric materials have attracted great attention because of their scalable processability and great potential for powering flexible electronics, but it is challenging to integrate mechanical flexibility, solution-printability and outstanding thermoelectric properties together. In particular, such an n-type thermoelectric material is highly sought after. In this paper, 2D TiS 2 nanosheets were exfoliated from layered polycrystalline powders, and then assembled with C 60 nanoparticles, resulting in a new class of flexible n-type thermoelectric materials via a concurrent enhancement in the power factor and a reduction in thermal conductivity. The resultant C 60 /TiS 2 hybrid films show a ZT ∼ 0.3 at 400 K, far superior to the state-of-the-art solution-printable and flexible n-type thermoelectric materials. In particular, such a thermoelectric property rivals that of single-crystal TiS 2 -based thermoelectric materials, which are expensive, difficult to synthesize, and unsuitable for solution printing. A solution of the C 60 /TiS 2 hybrid was also used as an ink for printing large-area flexible and spatial thermoelectric devices. An outstanding output power of 1.68 W m −2 was generated at a temperature gradient of 20 K. This work paves the way for flexible, solution-printable, high-performance thermoelectric materials for flexible electronics.  more » « less
Award ID(s):
1634858
NSF-PAR ID:
10062080
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Energy & Environmental Science
Volume:
11
Issue:
5
ISSN:
1754-5692
Page Range / eLocation ID:
1307 to 1317
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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