Cited 10 time in webofscience Cited 11 time in scopus

Tellurium-evaporation-annealing for p-type bismuth-antimony-telluride thermoelectric materials

Title
Tellurium-evaporation-annealing for p-type bismuth-antimony-telluride thermoelectric materials
Authors
Kim, DH[Kim, Dong Hwan]Kwon, IH[Kwon, In Hye]Kim, C[Kim, Cham]Han, B[Han, Byungchan]Im, HJ[Im, Hee-Joong]Kim, H[Kim, Hoyoung]
DGIST Authors
Kim, DH[Kim, Dong Hwan]; Kwon, IH[Kwon, In Hye]; Kim, C[Kim, Cham]; Han, B[Han, Byungchan]; Kim, H[Kim, Hoyoung]
Issue Date
2013-01-25
Citation
Journal of Alloys and Compounds, 548, 126-132
Type
Article
Article Type
Article
Keywords
Ab Initio Density Functional Theories (DFT)AnnealingAnnealing MethodsAnti-Site DefectAntimony CompoundsBismuthBismuth Antimony TellurideBismuth CompoundsBulk AlloysCalculationsCarrier ConcentrationChemical CompositionsDensity Functional TheoryEvaporationExperimental MeasurementsFigure of MeritsNano ScaleP-TypePhase TransitionsSinteringTelluriumTellurium CompoundsThermo-ElectricThermo-Electric MaterialThermo-Electric PerformanceThermo-ElectricityUnderlying Mechanism
ISSN
0925-8388
Abstract
A tellurium evaporation annealing method has been investigated to control the carrier concentration of sintered (Bi,Sb)2Te3 compounds. Hot-pressed (Bi,Sb)2Te3 bulk alloys and tellurium powders located in an evacuated ampoule, were heated to 673 K and held for 3, 12 and 48 h. The crystal structure and chemical composition in the annealed specimens were preserved, while the carrier concentrations were varied between 1.53 × 1019 and 2.57 × 1019 cm -3, and the thermal conductivity at 300 K ranged between 1.20 and 1.25 W m-1 K-1. The figure of merit at 300 K was enhanced from 0.86 to 1.06 when the specimens were annealed for 3 h. To identify the underlying mechanism, we utilized ab initio density functional theory calculations. These computations indicated that a Te ad-layer on top of the Bi2Te3 energetically favors bulk Bi atoms to migrate to the surface. Our experimental measurements and the first-principles validations consistently indicate that the tellurium evaporation annealing method is a novel process for enhancing the thermoelectric performance of Bi-Te compounds by controlling their carrier concentrations, which is particularly useful in dealing with nano-scale composites. © 2012 Elsevier B.V. All rights reserved.
URI
http://hdl.handle.net/20.500.11750/2440
DOI
10.1016/j.jallcom.2012.08.130
Publisher
Elsevier
Related Researcher
Files:
There are no files associated with this item.
Collection:
Magnet-Controlled Materials Research Group1. Journal Articles
Department of Energy Science and EngineeringEnergy Systems Engineering1. Journal Articles


qrcode mendeley

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE