Journal ArticleDOI
Ultralow thermal conductivity and high thermoelectric figure of merit in SnSe crystals
Li-Dong Zhao,Shih Han Lo,Yongsheng Zhang,Hui Sun,Gangjian Tan,Ctirad Uher,Chris Wolverton,Vinayak P. Dravid,Mercouri G. Kanatzidis +8 more
TLDR
An unprecedented ZT of 2.6 ± 0.3 at 923 K is reported in SnSe single crystals measured along the b axis of the room-temperature orthorhombic unit cell, which highlights alternative strategies to nanostructuring for achieving high thermoelectric performance.Abstract:
The thermoelectric effect enables direct and reversible conversion between thermal and electrical energy, and provides a viable route for power generation from waste heat The efficiency of thermoelectric materials is dictated by the dimensionless figure of merit, ZT (where Z is the figure of merit and T is absolute temperature), which governs the Carnot efficiency for heat conversion Enhancements above the generally high threshold value of 25 have important implications for commercial deployment, especially for compounds free of Pb and Te Here we report an unprecedented ZT of 26 ± 03 at 923 K, realized in SnSe single crystals measured along the b axis of the room-temperature orthorhombic unit cell This material also shows a high ZT of 23 ± 03 along the c axis but a significantly reduced ZT of 08 ± 02 along the a axis We attribute the remarkably high ZT along the b axis to the intrinsically ultralow lattice thermal conductivity in SnSe The layered structure of SnSe derives from a distorted rock-salt structure, and features anomalously high Gruneisen parameters, which reflect the anharmonic and anisotropic bonding We attribute the exceptionally low lattice thermal conductivity (023 ± 003 W m(-1) K(-1) at 973 K) in SnSe to the anharmonicity These findings highlight alternative strategies to nanostructuring for achieving high thermoelectric performanceread more
Citations
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Journal ArticleDOI
Crystal structure and phase transition of thermoelectric SnSe
TL;DR: The evolution of lattice constants, fractional coordinates, site occupancy factors and atomic displacement factors with temperature is reported by means of high-resolution synchrotron powder X-ray diffraction measured from 100 to 855 K.
Journal ArticleDOI
Thermoelectric SnS and SnS-SnSe solid solutions prepared by mechanical alloying and spark plasma sintering: Anisotropic thermoelectric properties.
Asfandiyar,Tian-Ran Wei,Zhiliang Li,Fu-Hua Sun,Yu Pan,Chao-Feng Wu,Muhammad Farooq,Huaichao Tang,Fu Li,Bo Li,Jing-Feng Li +10 more
TL;DR: With increasing selenium content the formation of solid solutions substantially improved the electrical conductivity due to the increased carrier concentration and the optimized power factor and reduced thermal conductivity resulted in a maximum ZT value of 0.64 at 823 K.
Journal ArticleDOI
Recent developments in flexible thermoelectrics: From materials to devices
TL;DR: In this article, a review of recent advances achieved in wide thermoelectric (TE) related technologies are reviewed from the view of materials to devices, including the specific structural designs and working principles of the FTE devices, the properties of the materials involved, the manufacturing strategies for device assembly, and their real functioning performances.
Journal ArticleDOI
Ultra-high average figure of merit in synergistic band engineered SnxNa1−xSe0.9S0.1 single crystals
Kunling Peng,Kunling Peng,Bin Zhang,Hong Wu,Hong Wu,Xianlong Cao,Ang Li,Dingfeng Yang,Xu Lu,Guoyu Wang,Xiaodong Han,Ctirad Uher,Xiaoyuan Zhou +12 more
TL;DR: In this paper, the authors report a series of record high zTave over a wide temperature range, approaching ∼1.60 in the range from 300 to 923 K in Na-doped SnSe0.9S0.03Se 0.1 single crystals.
Journal ArticleDOI
High-temperature oxidation behavior of thermoelectric SnSe
TL;DR: In this paper, the oxidation behavior of SnSe at four temperatures between 600°C and 700°C in atmospheric air was investigated by monitoring the weight change as a function of time, as well as by characterizing the oxidized samples using optical microscopy, SEM with EDS, and powder XRD.
References
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Hendrik J. Monkhorst,J.D. Pack +1 more
TL;DR: In this article, a method for generating sets of special points in the Brillouin zone which provides an efficient means of integrating periodic functions of the wave vector is given, where the integration can be over the entire zone or over specified portions thereof.
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TL;DR: A new era of complex thermoelectric materials is approaching because of modern synthesis and characterization techniques, particularly for nanoscale materials, and the strategies used to improve the thermopower and reduce the thermal conductivity are reviewed.
Journal ArticleDOI
High-performance bulk thermoelectrics with all-scale hierarchical architectures
Kanishka Biswas,Jiaqing He,Ivan Blum,Ivan Blum,Chun I. Wu,Timothy P. Hogan,Timothy P. Hogan,David N. Seidman,Vinayak P. Dravid,Mercouri G. Kanatzidis,Mercouri G. Kanatzidis +10 more
TL;DR: It is shown that heat-carrying phonons with long mean free paths can be scattered by controlling and fine-tuning the mesoscale architecture of nanostructured thermoelectric materials, and an increase in ZT beyond the threshold of 2 highlights the role of, and need for, multiscale hierarchical architecture in controlling phonon scattering in bulk thermoeLECTrics.