Journal ArticleDOI
Measurements of anisotropic thermoelectric properties in superlattices
TLDR
In this paper, a two-wire 3ω method is employed to measure the in-plane and cross-plane thermal conductivities of an n-type Si(80 A)/Ge(20 A) superlattice.Abstract:
Thermoelectric properties, i.e., thermal conductivity, electrical conductivity, and the Seebeck coefficient, have been measured in the directions parallel (in-plane) and perpendicular to the interface of an n-type Si(80 A)/Ge(20 A) superlattice. A two-wire 3ω method is employed to measure the in-plane and cross-plane thermal conductivities. The cross-plane Seebeck coefficient is deduced by using a differential measurement between the superlattice and reference samples and the cross-plane electrical conductivity is determined through a modified transmission-line method. The in-plane thermal conductivity of the Si/Ge superlattice is 5–6 times higher than the cross-plane one, and the electrical conductivity shows a similar anisotropy. The anisotropy of the Seebeck coefficients is smaller in comparison to electrical and thermal conductivities in the temperature range from 150 to 300 K. However, the cross-plane Seebeck coefficient rises faster with increasing temperature than that of the in-plane direction.read more
Citations
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Journal ArticleDOI
Enhancement of Thermoelectric Figure-of-Merit by a Bulk Nanostructuring Approach
TL;DR: In this paper, the synthesis process and the relationship between the microstructures and the thermoelectric properties of the nanostructured bulk materials with an enhanced ZT value are reviewed.
Journal ArticleDOI
Enhanced thermoelectric figure of merit in nanostructured n-type silicon germanium bulk alloy
Xiaowei Wang,Hohyun Lee,Yucheng Lan,Gaohua Zhu,Giri Joshi,Dezhi Wang,Jian Yang,Andrew Muto,M. Y. Tang,J. Klatsky,S. Song,Mildred S. Dresselhaus,Gang Chen,Zhensong Ren +13 more
TL;DR: In this paper, a peak ZT of about 1.3 at 900°C in an n-type nanostructured SiGe bulk alloy has been achieved by using a nanostructure approach, mainly due to a reduction in the thermal conductivity caused by the enhanced phonon scattering off the increased density of nanograin boundaries.
Journal ArticleDOI
Highly Thermally Conductive Papers with Percolative Layered Boron Nitride Nanosheets
Hongli Zhu,Yuanyuan Li,Zhiqiang Fang,Jiajun Xu,Fangyu Cao,Jiayu Wan,Colin Preston,Bao Yang,Liangbing Hu +8 more
TL;DR: A dielectric nanocomposite paper with layered boron nitride (BN) nanosheets wired by one-dimensional (1D) nanofibrillated cellulose (NFC) that has superior thermal and mechanical properties is reported.
Journal ArticleDOI
Nanoscale heat transfer – from computation to experiment
Tengfei Luo,Gang Chen +1 more
TL;DR: This review will first discuss recent advances in computational and experimental methods used in nanoscale thermal transport studies, followed by reviews of novel thermal transport phenomena at the nanoscales observed in both computational and Experimental studies, and discussion on current understanding of these novel phenomena.
Journal ArticleDOI
Recent Progress of Two-Dimensional Thermoelectric Materials
Delong Li,Youning Gong,Yue-Xing Chen,Jiamei Lin,Qasim Khan,Yupeng Zhang,Yu Li,Han Zhang,Heping Xie +8 more
TL;DR: A comprehensive review on the recent development of two-dimensional (2D) nanomaterials for bulk or thin-film thermoelectric materials, as well as composite filler, has been extensively presented.
References
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Journal ArticleDOI
Thin-film thermoelectric devices with high room-temperature figures of merit
TL;DR: Th thin-film thermoelectric materials are reported that demonstrate a significant enhancement in ZT at 300 K, compared to state-of-the-art bulk Bi2Te3 alloys, and the combination of performance, power density and speed achieved in these materials will lead to diverse technological applications.
Journal ArticleDOI
Effect of quantum-well structures on the thermoelectric figure of merit.
TL;DR: In this article, the authors proposed to use quantum-well superlattice structures to enhance the performance of thermoelectric coolers and showed that layering has the potential to increase significantly the figure of merit of a highly anisotropic material.
Journal ArticleDOI
Thermal conductivity and ballistic-phonon transport in the cross-plane direction of superlattices
TL;DR: In this paper, a model of the thermal conductivity and phonon transport in the direction perpendicular to the film plane of superlattices is established based on solving the phonon Boltzmann transport equation (BTE).