A Computational Survey of Semiconductors for Power Electronics

Power electronics (PE) are used to control and convert electrical energy in a wide range of applications from consumer products to large-scale industrial equipment. While Si-based power devices account for the vast majority of the market, wide band gap semiconductors such as SiC, GaN, and Ga2O3 are starting to gain ground. However, these emerging materials face challenges due to either non-negligible defect densities, or high synthesis and processing costs, or poor thermal properties. Here, we report on a broad computational survey aimed to identify promising materials for future power electronic devices beyond SiC, GaN, and Ga2O3. We consider 863 oxides, sulfides, nitrides, carbides, silicides, and borides that are reported in the crystallographic database and exhibit finite calculated band gaps. We utilize ab initio methods in conjunction with models for intrinsic carrier mobility, and critical breakdown field to compute the widely used Baliga figure of merit. We also compute the lattice thermal conductivity as a screening parameter. In addition to correctly identifying known PE materials, our survey has revealed a number of promising candidates exhibiting the desirable combination of high figure of merit and high lattice thermal conductivity, which we propose for further experimental investigations.

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Local ferroelectric polarization switching driven by nanoscale distortions in thermoelectric $${\text {Sn}}_{0.7}{\text {Ge}}_{0.3}{\text {Te}}$$

Scientific Reports ◽

10.1038/s41598-021-96299-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Aastha Vasdev ◽

Moinak Dutta ◽

Shivam Mishra ◽

Veerpal Kaur ◽

Harleen Kaur ◽

...

Keyword(s):

Thermal Conductivity ◽

Figure Of Merit ◽

Room Temperature ◽

Lattice Thermal Conductivity ◽

Direct Evidence ◽

Temperature Dependent ◽

Force Microscopy ◽

Ferroelectric Domains ◽

Pdf Analysis ◽

Ferroelectric Transition Temperature

AbstractA remarkable decrease in the lattice thermal conductivity and enhancement of thermoelectric figure of merit were recently observed in rock-salt cubic SnTe, when doped with germanium (Ge). Primarily, based on theoretical analysis, the decrease in lattice thermal conductivity was attributed to local ferroelectric fluctuations induced softening of the optical phonons which may strongly scatter the heat carrying acoustic phonons. Although the previous structural analysis indicated that the local ferroelectric transition temperature would be near room temperature in $${\text {Sn}}_{0.7}{\text {Ge}}_{0.3}{\text {Te}}$$ Sn 0.7 Ge 0.3 Te , a direct evidence of local ferroelectricity remained elusive. Here we report a direct evidence of local nanoscale ferroelectric domains and their switching in $${\text {Sn}}_{0.7}{\text {Ge}}_{0.3}{\text {Te}}$$ Sn 0.7 Ge 0.3 Te using piezoeresponse force microscopy(PFM) and switching spectroscopy over a range of temperatures near the room temperature. From temperature dependent (250–300 K) synchrotron X-ray pair distribution function (PDF) analysis, we show the presence of local off-centering distortion of Ge along the rhombohedral direction in global cubic $${\text {Sn}}_{0.7}{\text {Ge}}_{0.3}{\text {Te}}$$ Sn 0.7 Ge 0.3 Te . The length scale of the $${\text {Ge}}^{2+}$$ Ge 2 + off-centering is 0.25–0.10 Å near the room temperatures (250–300 K). This local emphatic behaviour of cation is the cause for the observed local ferroelectric instability, thereby low lattice thermal conductivity in $${\text {Sn}}_{0.7}{\text {Ge}}_{0.3}{\text {Te}}$$ Sn 0.7 Ge 0.3 Te .

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Investigation of Thermoelectric Materials: Substitution effect of Bi on the Ag1-xPb18MTe20 (M = Sb, Bi) (x = 0, 0.14, 0.3)

MRS Proceedings ◽

10.1557/proc-1044-u03-14 ◽

2007 ◽

Vol 1044 ◽

Author(s):

Mi-kyung Han ◽

Huijun Kong ◽

Ctirad Uher ◽

Mercouri G Kanatzidis

Keyword(s):

Thermal Conductivity ◽

Electrical Conductivity ◽

Seebeck Coefficient ◽

Thermoelectric Materials ◽

Figure Of Merit ◽

Lattice Thermal Conductivity ◽

Substitution Effect ◽

Dimensionless Figure Of Merit ◽

The Matrix ◽

Mass Fluctuation

AbstractWe performed comparative investigations of the Ag1-xPb18MTe20 (M = Bi, Sb) (x = 0, 0.14, 0.3) system to better understand the roles of Sb and Bi on the thermoelectric properties. In both systems, the electrical conductivity nearly keeps the same values, while the Seebeck coefficient decreases dramatically in going from Sb to Bi. Compared to the lattice thermal conductivity of PbTe, that of AgPb18BiTe20 is substantially reduced. The lattice thermal conductivity of the Bi analog, however, is higher than that of AgPb18SbTe20 and this is attributed largely to the decrease in the degree of mass fluctuation between the nanostructures and the matrix (for the Bi analog). As a result the dimensionless figure of merit ZT of Ag1-xPb18MTe20 (M = Bi) is found to be smaller than that of Ag1-xPb18MTe20 (M = Sb).

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Low lattice thermal conductivity and high figure of merit in n‐type doped full‐Heusler compounds X 2 YAu (X = Sr, Ba; Y = as, Sb)

International Journal of Energy Research ◽

10.1002/er.7154 ◽

2021 ◽

Author(s):

Weiqiang Wang ◽

Zhenhong Dai ◽

Xichang Wang ◽

Qi Zhong ◽

Yinchang Zhao ◽

...

Keyword(s):

Thermal Conductivity ◽

Figure Of Merit ◽

Lattice Thermal Conductivity ◽

Heusler Compounds ◽

High Figure ◽

Full Heusler

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Effects of Ce filling fraction and Fe content on the thermoelectric properties of Co-rich CeyFexCo4−xSb12

Journal of Materials Research ◽

10.1557/jmr.2001.0109 ◽

2001 ◽

Vol 16 (3) ◽

pp. 837-843 ◽

Cited By ~ 66

Author(s):

Xinfeng Tang ◽

Lidong Chen ◽

Takashi Goto ◽

Toshio Hirai

Keyword(s):

Thermal Conductivity ◽

Thermoelectric Properties ◽

Figure Of Merit ◽

Single Phase ◽

Lattice Thermal Conductivity ◽

Hole Concentration ◽

Thermoelectric Figure Of Merit ◽

Thermoelectric Figure ◽

Filling Fraction ◽

Fe Content

Single-phase filled skutterudite compounds, CeyFexCo4−xSb12 (x = 0 to 3.0, y = 0 to 0.74), were synthesized by a melting method. The effects of Fe content and Ce filling fraction on the thermoelectric properties of CeyFexCo4−xSb12 were investigated. The lattice thermal conductivity of Ce-saturated CeyFexCo4−xSb12, y being at the maximum corresponding to x, decreased with increasing Fe content (x) and reached its minimum at about x = 1.5. When x was 1.5, lattice thermal conductivity decreased with increasing Ce filling fraction till y = 0.3 and then began to increase after reaching the minimum at y = 0.3. Hole concentration and electrical conductivity of Cey Fe1.5Co2.5Sb12 decreased with increasing Ce filling fraction. The Seebeck coefficient increased with increasing Ce filling fraction. The greatest dimensionless thermoelectric figure of merit T value of 1.1 was obtained at 750 K for the composition of Ce0.28Fe1.52Co2.48Sb12.

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Thermoelectric Properties of K2Bi8−xSbxSe13Solid Solutions and Se Doping

MRS Proceedings ◽

10.1557/proc-691-g13.2 ◽

2001 ◽

Vol 691 ◽

Author(s):

Theodora Kyratsi ◽

Jeffrey S. Dyck ◽

Wei Chen ◽

Duck-Young Chung ◽

Ctirad Uher ◽

...

Keyword(s):

Thermal Conductivity ◽

Charge Transport ◽

Transport Properties ◽

Thermoelectric Properties ◽

Solid Solutions ◽

Figure Of Merit ◽

Lattice Thermal Conductivity ◽

Se Doping ◽

Mass Fluctuation ◽

Thermal Conductivities

ABSTRACTOur efforts to improve the thermoelectric properties of β-K2Bi8Se13, led to systematic studies of solid solutions of the type β-K2Bi8−xSbxSe13. The charge transport properties and thermal conductivities were studied for selected members of the series. Lattice thermal conductivity decreases due to the mass fluctuation generated in the lattice by the mixed occupation of Sb and Bi atoms. Se excess as a dopant was found to increase the figure-of merit of the solid solutions.

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An Investigation of Hydrological Effects on the Thermal Performance of Standing Column Well Using the in-situ Thermal Response Test

International Journal of Air-Conditioning and Refrigeration ◽

10.1142/s2010132519500159 ◽

2019 ◽

Vol 27 (02) ◽

pp. 1950015 ◽

Cited By ~ 1

Author(s):

Keun Sun Chang ◽

Young Jae Kim ◽

Min Jun Kim

Keyword(s):

Thermal Conductivity ◽

Thermal Resistance ◽

Flow Rate ◽

Large Scale ◽

Thermal Response ◽

Thermal Response Test ◽

Response Test ◽

Geological Conditions ◽

Wide Range ◽

Borehole Thermal Resistance

The standing column well (SCW) for ground source heat pump (GSHP) systems is a highly promising technology with its high heat capacity and efficiency. In this study, a large-scale thermal response tester has been built, which is capable of imposing a wide range of heat on the SCW ground heat exchangers and measuring time responses of their thermal parameters. Two standing column wells in one site but with different well hydrological and geological conditions are tested to study their effects on the thermal performances. Borehole thermal resistance ([Formula: see text]) and the effective thermal conductivity ([Formula: see text]) are derived from data obtained from the thermal response test (TRT) by using a line source method. Results show that the influence of groundwater movement on the thermal conductivity of the SCW is not very significant (3.6% difference between two different geological conditions). This indicates that results of one TRT measurement can be applied to other SCWs in the same site, with which considerable time and cost are saved. The increase of circulation flow rate enhances the ground thermal conductivity moderately (4.5% increase with flow rate increase of 45%), but the borehole thermal resistance is substantially lowered (about 25.9%).

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Low lattice thermal conductivity and high thermoelectric figure of merit in Na2MgSn

Physical Review B ◽

10.1103/physrevb.99.024310 ◽

2019 ◽

Vol 99 (2) ◽

Cited By ~ 1

Author(s):

Cong Wang ◽

Y. B. Chen ◽

Shu-Hua Yao ◽

Jian Zhou

Keyword(s):

Thermal Conductivity ◽

Figure Of Merit ◽

Lattice Thermal Conductivity ◽

Thermoelectric Figure Of Merit ◽

Thermoelectric Figure

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Thermoelectric Properties of CoSb3-based Skutterudite Compounds

MRS Proceedings ◽

10.1557/proc-1267-dd03-02 ◽

2010 ◽

Vol 1267 ◽

Author(s):

Adul Harnwunggmoung ◽

Ken Kurosaki ◽

Hiroaki Muta ◽

Shinsuke Yamanaka

Keyword(s):

Thermal Conductivity ◽

Thermoelectric Properties ◽

Figure Of Merit ◽

Room Temperature ◽

Lattice Thermal Conductivity ◽

Filling Ratio ◽

Thermoelectric Figure Of Merit ◽

Thermoelectric Figure ◽

Alloy Scattering ◽

Skutterudite Compound

AbstractCoSb3 is known as a skutterudite compound that could exhibit high thermoelectric figure of merit. However, the thermal conductivity of CoSb3 is relatively high. In order to enhance the thermoelectric performance of this compound, we tried to reduce the thermal conductivity of CoSb3 by substitution of Rh for Co and by Tl-filling into the voids. The polycrystalline samples of (Co,Rh)Sb3 and Tl-filled CoSb3 were prepared and the thermoelectric properties such as the Seebeck coefficient, electrical resistivity, and thermal conductivity were measured in the temperature range from room temperature to 750 K. The Rh substitution for Co reduced the lattice thermal conductivity, due to the alloy scattering effect. The minimum value of the lattice thermal conductivity was 4 Wm-1K-1 at 750 K obtained for (Co0.7Rh0.3)Sb3. Also the lattice thermal conductivity rapidly decreased with increasing the Tl-filling ratio. T10.25Co4Sb12 exhibited the best ZT values; the maximum ZT was 0.9 obtained at 600 K.

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