Open AccessJournal Article
Enhanced Thermoelectric Performance in Rough Silicon Nanowires
Renkun Chen,Allon I. Hochbaum,Raul Diaz Delgado,Wenjie Liang,Erik C. Garnett,Mark Najarian,Arun Majumdar,Peidong Yang +7 more
TLDR
Electrochemical synthesis of large-area, wafer-scale arrays of rough Si nanowires that are 20–300 nm in diameter show promise as high-performance, scalable thermoelectric materials.Abstract:
Approximately 90 per cent of the world’s power is generated by heat engines that use fossil fuel combustion as a heat source and typically operate at 30–40 per cent efficiency, such that roughly 15 terawatts of heat is lost to the environment. Thermoelectric modules could potentially convert part of this low-grade waste heat to electricity. Their efficiency depends on the thermoelectric figure of merit ZT of their material components, which is a function of the Seebeck coefficient, electrical resistivity, thermal conductivity and absolute temperature. Over the past five decades it has been challenging to increase ZT > 1, since the parameters of ZT are generally interdependent. While nanostructured thermoelectric materials can increase ZT > 1 (refs 2–4), the materials (Bi, Te, Pb, Sb, and Ag) and processes used are not often easy to scale to practically useful dimensions. Here we report the electrochemical synthesis of large-area, wafer-scale arrays of rough Si nanowires that are 20–300 nm in diameter. These nanowires have Seebeck coefficient and electrical resistivity values that are the same as doped bulk Si, but those with diameters of about 50 nm exhibit 100-fold reduction in thermal conductivity, yielding ZT = 0.6 at room temperature. For such nanowires, the lattice contribution to thermal conductivity approaches the amorphous limit for Si, which cannot be explained by current theories. Although bulk Si is a poor thermoelectric material, by greatly reducing thermal conductivity without much affecting the Seebeck coefficient and electrical resistivity, Si nanowire arrays show promise as high-performance, scalable thermoelectric materials.read more
Citations
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Complex thermoelectric materials.
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.
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Cooling, heating, generating power, and recovering waste heat with thermoelectric systems.
TL;DR: Thermoelectric materials are solid-state energy converters whose combination of thermal, electrical, and semiconductor properties allows them to be used to convert waste heat into electricity or electrical power directly into cooling and heating.
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Prospects of Colloidal Nanocrystals for Electronic and Optoelectronic Applications
TL;DR: Nanocrystals (NCs) discussed in this Review are tiny crystals of metals, semiconductors, and magnetic material consisting of hundreds to a few thousand atoms each that are among the hottest research topics of the last decades.
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Enhancement of Thermoelectric Efficiency in PbTe by Distortion of the Electronic Density of States
Joseph P. Heremans,Vladimir Jovovic,Eric S. Toberer,Ali Saramat,Ken Kurosaki,Anek Charoenphakdee,Shinsuke Yamanaka,G. Jeffrey Snyder +7 more
TL;DR: A successful implementation through the use of the thallium impurity levels in lead telluride (PbTe) is reported, which results in a doubling of zT in p-type PbTe to above 1.5 at 773 kelvin.
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Bulk nanostructured thermoelectric materials: current research and future prospects
TL;DR: In this paper, the authors introduce the principles and present status of bulk nanostructured materials, then describe some of the unanswered questions about carrier transport and how current research is addressing these questions.
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.
BookDOI
CRC Handbook of Thermoelectrics
TL;DR: In this article, Rowe et al. proposed a method for reducing the thermal conductivity of a thermoelectric generator by reducing the carrier concentration of the generator, which was shown to improve the generator's performance.
Journal ArticleDOI
Cubic AgPbmSbTe2+m: Bulk Thermoelectric Materials with High Figure of Merit
Kuei Fang Hsu,Sim Loo,Fu Guo,Wei Chen,Jeffrey S. Dyck,Ctirad Uher,Timothy P. Hogan,Efstathios K. Polychroniadis,Mercouri G. Kanatzidis +8 more
TL;DR: In the temperature range 600 to 900 kelvin, the AgPbmSbTe2+m material is expected to outperform all reported bulk thermoelectrics, thereby earmarking it as a material system for potential use in efficient thermoeLECTric power generation from heat sources.
Journal ArticleDOI
Quantum dot superlattice thermoelectric materials and devices.
TL;DR: It is demonstrated that improved cooling values relative to the conventional bulk (Bi,Sb)2(Se,Te)3thermoelectric materials using a n-type film in a one-leg thermoelectrics device test setup, which cooled the cold junction 43.7 K below the room temperature hot junction temperature of 299.8 K.