Giant improvement of thermoelectric power factor of Bi2Te3 under pressure

Abstract

The pressure ͑P͒ dependencies of both the thermopower ͑Seebeck effect͒ S and the electrical resistance ͑R͒ for p-type single crystals of Bi 2 Te 3 and indium-doped bismuth telluride ͑In x Bi 2−x Te 3 , 0.04Յ x Յ 0.10͒ are reported on a pressure range of 0-8.5 GPa. The thermoelectric power factor ͑efficiency͒ ͑ae = S 2 / R͒ exhibits two maxima: the first one near ϳ1 GPa and the second near ϳ2.5-4.5 GPa. These features evidence a giant increase in the power factor by a factor of ϳ10. Possible values of the dimensionless figure of merit under pressure are also estimated. The maxima are explained in terms of pressure-driven changes in an electron structure. The second feature may be also addressed to an intermediate high-pressure phase detected in x-ray diffraction studies.

Assessing the Thermoelectric Properties of Sintered Compounds via High-ThroughputAb-InitioCalculations

“…At room temperature, the state-of-the-art Bi 2 Te 3 compound has been reported to yield power factor as high as P ? ¼ 66:1 W=cmK 2 [62]. Although most compounds in our list have P lower than this value when L is a few nm, there are still some with P comparable to Bi 2 Te 3 .…”

Improved Electronic Structure and Optical Performance of Bi2Te3-xSex From First-principle Calculations Within TB-mBJ Exchange Potential

“…Figure 13 shows the optical conductivity σ (ω) of Bi 2 Te 3 -xSex for a different concentration (x), sharp peak is visible for every Selenide (Se) composition located at 3.4150 eV and 3.6055 eV respectively, also, it is shown that after 18.57 eV the reflectivity decreases dramatically and tends towards zero. The bowing parameter of The static reflectivity constants (the zero frequency limits) R(0) is determined by fitting the non linear variation, Relation (15) show the result: (15) Our results exhibit a negligible bowing parameter for the static reflectivity constant R(0), which has a bowing parameter b = 0.0022.…”

“…During last decennaries, these compounds have been extensively studied to advance their thermoelectric and optical properties by different aspect technological like doping, high-pressure and variation in mesostructure [2][3][4][5] . Structural, electrical and optical properties of Bi 2 Se 3 and Bi 2 Se (3x-1) Te x thin films have been studied experimentally 6 .…”

Raman signatures of pressure induced electronic topological and structural transitions in Bi2Te3

“…Bismuth telluride (Bi 2 Te 3 ) has been shown to be one of the simplest three dimensional (3-D) topological insulators, [1,2] an extraordinary thermoelectric compound at ambient temperature [3][4][5] and a possible topological superconductor [6]. More recently, atomicallythin layers have also been isolated by mechanical exfoliation from bulk Bi 2 Te 3 in a "graphene-like" fashion for enhanced thermoelectric properties [7].…”