Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA 22904, USA.
Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA 22904, USA.
Sci Adv. 2019 Nov 8;5(11):eaax7827. doi: 10.1126/sciadv.aax7827. eCollection 2019 Nov.
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-graphene-gold structures computationally and experimentally. Graphene and WSe layers were stacked, followed by deposition of gold contacts. The - curve of the structure suggests near-ohmic contact. A hybrid technique that combines thermoreflectance and cooling curve measurements is used to extract the device . The measured Seebeck coefficient, thermal and electrical conductance, and 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.
基于范德华结构的固态热离子器件被提出用于纳米尺度的热能到电能转换和集成电子冷却应用。我们通过计算和实验研究了金-石墨烯-WSe2-石墨烯-金结构的热离子冷却。先堆叠石墨烯和 WSe2 层，然后沉积金接触。结构的 I-V 曲线表明其为近欧姆接触。采用热反射率和冷却曲线测量相结合的混合技术来提取器件的 。在室温下测量的塞贝克系数、热和电导率以及 值与使用第一性原理计算结合实空间格林函数形式主义的理论预测相符。这项工作为高效热离子器件的开发奠定了基础。
