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DOI	10.1039/c9ee00317g
	Medium-temperature thermoelectric GeTe: Vacancy suppression and band structure engineering leading to high performance
	Dong J.; Sun F.-H.; Tang H.; Pei J.; Zhuang H.-L.; Hu H.-H.; Zhang B.-P.; Pan Y.; Li J.-F.
发表日期	2019
ISSN	17545692
起始页码	1396
结束页码	1403
卷号	12 期号:4
英文摘要	GeTe is a promising thermoelectric material at medium temperature, but its carrier concentration tends to go beyond the optimal range for thermoelectrics. This work realized a significant ZT enhancement from 1.0 to 2.0 by suppressing the formation of Ge vacancies and band convergence. By simply optimizing the amount of excessive Ge, the hole carrier concentration is greatly reduced. It is demonstrated that the suppression of Ge vacancies can not only optimize the carrier concentration but also recover the mobility to a high value of 90 cm2 V-1 s-1, which well exceeds the previously reported data and guarantees superior electrical transport properties, leading to a ZT of 1.6. Further Bi doping facilitates band convergence as featured by the increased band effective mass and high mobility, which in turn yields large power factors and low electronic thermal conductivity. Bi doping induced mass and strain fluctuation also favors the reduction of the lattice thermal conductivity. Consequently, a maximum ZT of ∼ 2.0 at 650 K with an average ZT of over 1.2 is achieved in the nominal composition Bi0.05Ge0.99Te, which is one of the best thermoelectric materials for medium temperature applications. © 2019 The Royal Society of Chemistry.
英文关键词	Germanium; Germanium compounds; High temperature engineering; Hole concentration; Strain; Tellurium compounds; Thermoelectric equipment; Thermoelectricity; Band structure engineering; Electrical transport properties; Electronic thermal conductivity; Lattice thermal conductivity; Medium temperature; Nominal composition; Strain fluctuations; Thermo-Electric materials; Thermal conductivity; concentration (composition); engineering; optimization; performance assessment; temperature effect
语种	英语
来源期刊	Energy & Environmental Science
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/189926
作者单位	State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China; Beijing Municipal Key Laboratory of New Energy Materials and Technologies, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, Dresden, 01187, Germany
推荐引用方式 GB/T 7714	Dong J.,Sun F.-H.,Tang H.,et al. Medium-temperature thermoelectric GeTe: Vacancy suppression and band structure engineering leading to high performance[J],2019,12(4).
APA	Dong J..,Sun F.-H..,Tang H..,Pei J..,Zhuang H.-L..,...&Li J.-F..(2019).Medium-temperature thermoelectric GeTe: Vacancy suppression and band structure engineering leading to high performance.Energy & Environmental Science,12(4).
MLA	Dong J.,et al."Medium-temperature thermoelectric GeTe: Vacancy suppression and band structure engineering leading to high performance".Energy & Environmental Science 12.4(2019).