Optimization of thermoelectric properties on Bi2Te3 thin films deposited by thermal co-evaporation

Gonçalves, L. M.; Couto, Carlos; Alpuim, P.; Rolo, Anabela G.; Völklein, F.; Correia, J. H.

doi:10.1016/j.tsf.2009.08.038

Cited by 211 publications

(126 citation statements)

References 16 publications

Supporting

Mentioning

108

Contrasting

Unclassified

Order By: Relevance

“…It is important to note that the Seebeck coefficients for both n-and p-type doped tellurium are quite large at room temperature, reaching a peak value of 450 μV/K at a hole concentration around 10 17 cm −3 and with an average value in the range of 200-250 μV/K. These values of S for a single-element solid compare favorably with those reported for optimized Bi 2 Te 3 [37]. The large Seebeck coefficient for tellurium is mainly due to the large asymmetry of the transport distribution function from the the staircaselike DOS shown in Fig.…”

Section: Resultssupporting

confidence: 71%

Elemental tellurium as a chiralp-type thermoelectric material

2014

View full text Add to dashboard Cite

The thermoelectric transport properties of elemental tellurium are investigated by density functional theory combined with the Boltzmann transport equation in the rigid band approximation. We find that the thermoelectric transport properties parallel and perpendicular to the helical chains are highly asymmetric (almost symmetric) for p-(n-) type doped tellurium due to the anisotropic (isotropic) hole (electron) pockets of the Fermi surface. The electronic band structure shows that the lone-pair derived uppermost heavy-hole and extremely light-hole lower valence bands offer the opportunity to obtain both a high Seebeck coefficient and electrical conductivity along the chains through Sb or Bi doping. Furthermore, the stairlike density of states yields a large asymmetry for the transport distribution function relative to the Fermi energy which leads to large thermopower. The calculations reveal that tellurium has the potential to be a good p-type thermoelectric material with an optimum figure of merit zT of 0.31 (0.56) at room temperature (500 K) at a hole concentration around 1 × 10 19 cm −3 . Exploiting the rich chemistry of lone pairs in chiral solids may have important implications for the discovery of high-zT polychalcogenide-based thermoelectric materials.

show abstract

Section: Resultssupporting

confidence: 71%

Elemental tellurium as a chiralp-type thermoelectric material

2014

View full text Add to dashboard Cite

show abstract

“…9 These power factors are comparable to state of the art thermoelectric material such as pure Bi 2 Te 3 or PbTe. [10][11][12] The value is high considering that it is obtained for a nitride material without any deliberate optimization of doping and has been suggested to be related to electronic structure effects of nitrogen vacancies and oxygen incorporation. 9,13 However, for most practical applications, the thermoelectric figure of merit (ZT) of ScN is too low.…”

Section: à3mentioning

confidence: 99%

Phase stability of ScN-based solid solutions for thermoelectric applications from first-principles calculations

Kerdsongpanya

Alling

Eklund

2013

Journal of Applied Physics

View full text Add to dashboard Cite

We have used first-principles calculations to investigate the trends in mixing thermodynamics of ScN-based solid solutions in the cubic B1 structure. 13 different Sc1−xMxN (M = Y, La, Ti, Zr, Hf, V, Nb, Ta, Gd, Lu, Al, Ga, In) and three different ScN1−xAx (A = P, As, Sb) solid solutions are investigated and their trends for forming disordered or ordered solid solutions or to phase separate are revealed. The results are used to discuss suitable candidate materials for different strategies to reduce the high thermal conductivity in ScN-based systems, a material having otherwise promising thermoelectric properties for medium and high temperature applications. Our results indicate that at a temperature of T = 800 °C, Sc1−xYxN; Sc1−xLaxN; Sc1−xGdxN, Sc1−xGaxN, and Sc1−xInxN; and ScN1−xPx, ScN1−xAsx, and ScN1−xSbx solid solutions have phase separation tendency, and thus, can be used for forming nano-inclusion or superlattices, as they are not intermixing at high temperature. On the other hand, Sc1−xTixN, Sc1−xZrxN, Sc1−xHfxN, and Sc1−xLuxN favor disordered solid solutions at T = 800 °C. Thus, the Sc1−xLuxN system is suggested for a solid solution strategy for phonon scattering as Lu has the same valence as Sc and much larger atomic mass.

Funding Agencies|Swedish Research Council (VR)|621-2009-5258621-2012-4430621-2011-4417|Linnaeus Strong Research Environment LiLi-NFM||Swedish Foundation for Strategic Research||Linkoping Center in Nanoscience and technology (CeNano)||

show abstract

“…Thermoelectric p-type (Sb 2 Te 3 ) and n-type (Bi 2 Te 3 ) thin films with thickness of 5 lm with high figures of merit were obtained by a thermal co-evaporation method (Goncalves et al 2006) in a high-vacuum chamber with base pressure p = 3 9 10 -6 mbar. The substrate temperature and evaporation rates were controlled during all the deposition process in order to obtain the desired properties.…”

Section: Fabrication Of the Detectormentioning

confidence: 99%

Bi2Te3-Sb2Te3 on polymeric substrate for X-ray detectors based on the seebeck effect

2011

View full text Add to dashboard Cite

A theoretical and experimental basis for a x-ray detector concept, based on the conversion of x-rays into thermal energy is presented. The detector follows an indirect approach: the x-rays are first converted into thermal energy, which is then converted into electrical signals by the Seebeck effect. The detector does not need high operating voltages as the detectors based on photoconductors, it shows higher efficiency in energy conversion than x-ray detectors based on scintillators and it has a better intrinsic signal to noise ratio than both photoconductor and scintillator methods. Moreover, this technique allows the fabrication of x-ray detectors on polymeric substrates, which is not so viable with the other aforementioned methods. As a drawback, the frequency response of this detector is usually low. This drawback can be overcome by reducing the mass of the detector.

show abstract

Optimization of thermoelectric properties on Bi2Te3 thin films deposited by thermal co-evaporation

Cited by 211 publications

References 16 publications

Elemental tellurium as a chiralp-type thermoelectric material

Elemental tellurium as a chiralp-type thermoelectric material

Phase stability of ScN-based solid solutions for thermoelectric applications from first-principles calculations

Bi2Te3-Sb2Te3 on polymeric substrate for X-ray detectors based on the seebeck effect

Contact Info

Product

Resources

About