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Title: Thermionic transport across gold-graphene-WSe 2 van der Waals heterostructures
Solid-state thermionic devices based on van der Waals structures were proposed for nanoscale thermal to electrical energy conversion and integrated electronic cooling applications. We study thermionic cooling across gold-graphene-WSe 2 -graphene-gold structures computationally and experimentally. Graphene and WSe 2 layers were stacked, followed by deposition of gold contacts. The I - V curve of the structure suggests near-ohmic contact. A hybrid technique that combines thermoreflectance and cooling curve measurements is used to extract the device ZT . The measured Seebeck coefficient, thermal and electrical conductance, and ZT values at room temperatures are in agreement with the theoretical predictions using first-principles calculations combined with real-space Green’s function formalism. This work lays the foundation for development of efficient thermionic devices.  more » « less
Award ID(s):
1653268
PAR ID:
10130027
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
5
Issue:
11
ISSN:
2375-2548
Page Range / eLocation ID:
eaax7827
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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