气候变化领域集成服务门户(CCPortal): Electron mean-free-path filtering in Dirac material for improved thermoelectric performance

CCPortal

DOI	10.1073/pnas.1715477115
	Electron mean-free-path filtering in Dirac material for improved thermoelectric performance
	Liu T.-H.; Zhou J.; Li M.; Ding Z.; Song Q.; Liao B.; Fu L.; Chen G.
发表日期	2018
ISSN	0027-8424
起始页码	879
结束页码	884
卷号	115 期号:5
英文摘要	Recent advancements in thermoelectric materials have largely benefited from various approaches, including band engineering and defect optimization, among which the nanostructuring technique presents a promising way to improve the thermoelectric figure of merit (zT) by means of reducing the characteristic length of the nanostructure, which relies on the belief that phonons’ mean free paths (MFPs) are typically much longer than electrons’. Pushing the nanostructure sizes down to the length scale dictated by electron MFPs, however, has hitherto been overlooked as it inevitably sacrifices electrical conduction. Here we report through ab initio simulations that Dirac material can overcome this limitation. The monotonically decreasing trend of the electron MFP allows filtering of long-MFP electrons that are detrimental to the Seebeck coefficient, leading to a dramatically enhanced power factor. Using SnTe as a material platform, we uncover this MFP filtering effect as arising from its unique nonparabolic Dirac band dispersion. Room-temperature zT can be enhanced by nearly a factor of 3 if one designs nanostructures with grain sizes of ∼10 nm. Our work broadens the scope of the nanostructuring approach for improving the thermoelectric performance, especially for materials with topologically nontrivial electronic dynamics.
英文关键词	Dirac material; Electron mean-free-path filtering; Electron–phonon interactions; Nanostructuring approach; Thermoelectrics
语种	英语
scopus关键词	chemical compound; tin telluride; unclassified drug; ab initio calculation; Article; constants and coefficients; controlled study; density functional theory; dispersion; electricity; electron; electron transport; mean free path; phonon; physics; priority journal; room temperature; Seebeck coefficient; thermoelectric transport
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160548
作者单位	Liu, T.-H., Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States; Zhou, J., Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States; Li, M., Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States, Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States; Ding, Z., Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States; Song, Q., Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States; Liao, B., Department of Mechanical Engineering, University of California, Santa Barbara, CA 93106, United States; Fu, L., Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, United States; Chen, G., Department of Mechanical Engineering, Massach...
推荐引用方式 GB/T 7714	Liu T.-H.,Zhou J.,Li M.,et al. Electron mean-free-path filtering in Dirac material for improved thermoelectric performance[J],2018,115(5).
APA	Liu T.-H..,Zhou J..,Li M..,Ding Z..,Song Q..,...&Chen G..(2018).Electron mean-free-path filtering in Dirac material for improved thermoelectric performance.Proceedings of the National Academy of Sciences of the United States of America,115(5).
MLA	Liu T.-H.,et al."Electron mean-free-path filtering in Dirac material for improved thermoelectric performance".Proceedings of the National Academy of Sciences of the United States of America 115.5(2018).