Thermoelectric characteristics of X$$_2$$YH$$_2$$ monolayers (X=Si, Ge; Y=P, As, Sb, Bi): a first-principles study

AbstractEver since global warming emerged as a serious issue, the development of promising thermoelectric materials has been one of the main hot topics of material science. In this work, we provide an in-depth understanding of the thermoelectric properties of X$$_2$$ 2 YH$$_2$$ 2 monolayers (X=Si, Ge; Y=P, As, Sb, Bi) using the density functional theory combined with the Boltzmann transport equation. The results indicate that the monolayers have very low lattice thermal conductivities in the range of 0.09−0.27 Wm$$^{-1}$$ - 1 K$$^{-1}$$ - 1 at room temperature, which are correlated with the atomic masses of primitive cells. Ge$$_2$$ 2 PH$$_2$$ 2 and Si$$_2$$ 2 SbH$$_2$$ 2 possess the highest mobilities for hole (1894 cm$$^2$$ 2 V$$^{-1}$$ - 1 s$$^{-1}$$ - 1 ) and electron (1629 cm$$^2$$ 2 V$$^{-1}$$ - 1 s$$^{-1}$$ - 1 ), respectively. Si$$_2$$ 2 BiH$$_2$$ 2 shows the largest room-temperature figure of merit, $$ZT=2.85$$ Z T = 2.85 in the n-type doping ( $$\sim 3\times 10^{12}$$ ∼ 3 × 10 12 cm$$^{-2}$$ - 2 ), which is predicted to reach 3.49 at 800 K. Additionally, Si$$_2$$ 2 SbH$$_2$$ 2 and Si$$_2$$ 2 AsH$$_2$$ 2 are found to have considerable ZT values above 2 at room temperature. Our findings suggest that the mentioned monolayers are more efficient than the traditional thermoelectric materials such as Bi$$_2$$ 2 Te$$_3$$ 3 and stimulate experimental efforts for novel syntheses and applications.

Download Full-text

Electronic, optical and thermoelectric properties of Fe2ZrP compound determined via first-principles calculations

RSC Advances ◽

10.1039/c9ra04736k ◽

2019 ◽

Vol 9 (44) ◽

pp. 25900-25911 ◽

Cited By ~ 3

Author(s):

Esmaeil Pakizeh ◽

Jaafar Jalilian ◽

Mahnaz Mohammadi

Keyword(s):

Density Functional Theory ◽

Thermoelectric Properties ◽

First Principles ◽

Density Functional ◽

Transport Theory ◽

First Principles Calculations ◽

Boltzmann Transport ◽

Functional Theory ◽

Boltzmann Transport Theory ◽

The Density Functional Theory

In this study, based on the density functional theory and semi-classical Boltzmann transport theory, we investigated the structural, thermoelectric, optical and phononic properties of the Fe2ZrP compound.

Download Full-text

Hybrid functional calculations of electronic and thermoelectric properties of GaS, GaSe, and GaTe monolayers

Physical Chemistry Chemical Physics ◽

10.1039/c8cp04723e ◽

2018 ◽

Vol 20 (45) ◽

pp. 28575-28582 ◽

Cited By ~ 19

Author(s):

Bhagwati Prasad Bahuguna ◽

L. K. Saini ◽

Rajesh O. Sharma ◽

Brajesh Tiwari

Keyword(s):

Density Functional Theory ◽

Transport Equation ◽

Thermoelectric Properties ◽

First Principles ◽

Density Functional ◽

Boltzmann Transport Equation ◽

Boltzmann Transport ◽

Hybrid Functional ◽

Functional Theory

We have investigated the structural, electronic and thermoelectric properties of GaS, GaSe and GaTe monolayers based on the first-principles approach by using density functional theory and the semi-classical Boltzmann transport equation.

Download Full-text

Ultralow and anisotropic thermal conductivity in semiconductor As2Se3

Physical Chemistry Chemical Physics ◽

10.1039/c7cp07242b ◽

2018 ◽

Vol 20 (3) ◽

pp. 1809-1816 ◽

Cited By ~ 6

Author(s):

Robert L. González-Romero ◽

Alex Antonelli ◽

Anderson S. Chaves ◽

Juan J. Meléndez

Keyword(s):

Thermal Conductivity ◽

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

Lattice Thermal Conductivity ◽

Boltzmann Transport Equation ◽

First Principles Calculations ◽

Boltzmann Transport ◽

Functional Theory ◽

Anisotropic Thermal Conductivity

An ultralow lattice thermal conductivity of 0.14 W m−1 K−1 along the b⃑ axis of As2Se3 single crystals was obtained at 300 K by first-principles calculations involving density functional theory and the resolution of the Boltzmann transport equation.

Download Full-text

Phase Stability in U-6Nb Alloy Doped with Ti from the First Principles Theory

Applied Sciences ◽

10.3390/app10103417 ◽

2020 ◽

Vol 10 (10) ◽

pp. 3417

Author(s):

Alexander Landa ◽

Per Söderlind ◽

Amanda Wu

Keyword(s):

Phase Stability ◽

First Principles ◽

Density Functional ◽

Room Temperature ◽

Rapid Quenching ◽

Quantum Mechanical ◽

First Principles Calculations ◽

Functional Theory ◽

The Density Functional Theory ◽

Effect Of Impurities

First-principles calculations within the density-functional-theory (DFT) approach are conducted in order to explore and explain the effect of small amounts of titanium on phase stability in the U-6Nb alloy. During rapid quenching from high to room temperature, metastable phases α′ (orthorhombic), α″ (monoclinic), and γ0 (tetragonal) can form, depending on Nb concentration. Important mechanical properties depend on the crystal structure and, therefore, an understanding of the effect of impurities on phase stability is essential. Insights on this issue are obtained from quantum-mechanical DFT calculations. The DFT framework does not rely on any material-specific assumptions and is therefore ideal for an unbiased investigation of the U-Nb system.

Download Full-text

FERROMAGNETIC PROPERTIES IN V-DOPED AlN FROM FIRST PRINCIPLES

Modern Physics Letters B ◽

10.1142/s0217984912501321 ◽

2012 ◽

Vol 26 (20) ◽

pp. 1250132

Author(s):

G. Y. YAO ◽

G. H. FAN ◽

J. H. MA ◽

S. W. ZHENG ◽

J. CHEN ◽

...

Keyword(s):

First Principles ◽

Density Functional ◽

Room Temperature ◽

Magnetic Semiconductor ◽

Double Exchange ◽

Functional Theory ◽

Zinc Blende ◽

The Density Functional Theory ◽

Spin Polarized ◽

Ferromagnetic Ground State

Using the first-principles method based on the density functional theory, we have calculated electronic structure of zinc blende AlN doped with 6.25% of V. The V dopants are found spin polarized and the calculated band structures suggest a 100% polarization of the conduction carriers. The ferromagnetic ground state in V-doped AlN can be explained in terms of double-exchange mechanism, and a Curie temperature above room temperature can be expected. These results suggest that the V-doped AlN may present a promising dilute magnetic semiconductor and find applications in the field of spintronics.

Download Full-text

The first-principles and BTE investigation of phonon transport in 1T-TiSe2

Physical Chemistry Chemical Physics ◽

10.1039/d0cp06333a ◽

2021 ◽

Author(s):

Zhao-Liang Wang ◽

Guofu Chen ◽

Xiaoliang Zhang ◽

Dawei Tang

Keyword(s):

Density Functional Theory ◽

Transport Equation ◽

First Principles ◽

Density Functional ◽

Boltzmann Transport Equation ◽

Phonon Transport ◽

Boltzmann Transport ◽

Functional Theory

Through the first-principles density functional theory and the phonon Boltzmann transport equation, we investigated the phonon transport characteristics inside 1T-TiSe2.

Download Full-text

Electric and Thermoelectric Properties of Cu12Sb4S13 Tetrahedrite with Impurities

10.20944/preprints201908.0051.v1 ◽

2019 ◽

Author(s):

Kamyar Ravaji ◽

Reza Ezzati ◽

Amir Hosein Mohammadi ◽

Seyed Amir Abbas

Keyword(s):

First Principles ◽

Figure Of Merit ◽

Density Functional ◽

Theoretical Study ◽

Complex Compounds ◽

First Principles Calculations ◽

Functional Theory ◽

The Density Functional Theory ◽

Electric Structure ◽

High Figure

The high figure of merit and earth abundance of Cu12Sb4S13 thermoelectric ma- terials have recently attracted many attentions toward these type of complex compounds. Intrinsic low thermal conductivity, as well as tunable electronic transport properties, make them suitable for thermoelectric power generation. In this study, we perform a comparative theoretical study on the substituted compounds, primarily at the Cu site including known tetrahedrite Cu12Sb4S13, by means of first-principles calculations. The density functional theory of electric structure is applied to investigate the result of substitution.

Download Full-text

Electronic and optical properties of GeS and GeS:Gd

International Journal of Modern Physics B ◽

10.1142/s0217979221503057 ◽

2021 ◽

Author(s):

A. O. Dashdemirov ◽

S. G. Asadullayeva ◽

A. S. Alekperov ◽

N. A. Ismayilova ◽

S. H. Jabarov

Keyword(s):

First Principles ◽

Density Functional ◽

Room Temperature ◽

Optical Transitions ◽

First Principles Calculations ◽

Functional Theory ◽

Noticeable Increase ◽

Semiconducting Properties ◽

The Density Functional Theory ◽

Layered Crystals

In this paper, the results of the first principles calculations within the framework of the density functional theory of the electronic spectrum of a GeS crystal are presented. The density of states and interband optical transitions are investigated. It was found that GeS compounds have semiconducting properties with a bandgap of 1.52 eV. The main contribution of the bands in the vicinity of the Fermi level is from the 3[Formula: see text] and 3[Formula: see text] states of the S and Ge atoms, respectively. The highest amplitude, about 2.3 eV ([Formula: see text], is mainly associated with the interband optical transitions between the states [Formula: see text]. The results of the luminescence studies of GeS and GeS:Gd layered crystals at room-temperature are presented. A noticeable increase in the intensity of the luminescence radiation in GeS:Gd has been established. The reason for the increase in the effectiveness of photoluminescence is due to the overlapping of optical transitions of GeS at 695 nm wavelength with the radiation lines of Gd[Formula: see text]ion at that same energy.

Download Full-text

Electron-phonon interaction in In-induced √7 ×√3 structures on Si(111) from first-principles

Physical Chemistry Chemical Physics ◽

10.1039/d0cp05234e ◽

2021 ◽

Author(s):

I. Yu. Sklyadneva ◽

Rolf Heid ◽

Pedro Miguel Echenique ◽

Evgueni Chulkov

Keyword(s):

Density Functional Theory ◽

Double Layer ◽

First Principles ◽

Linear Response ◽

Density Functional ◽

Single Layer ◽

Phonon Interaction ◽

Functional Theory ◽

Electron Phonon Interaction ◽

The Density Functional Theory

Electron-phonon interaction in the Si(111)-supported rectangular √(7 ) ×√3 phases of In is investigated within the density-functional theory and linear-response. For both single-layer and double-layer √(7 ) ×√3 structures, it...

Download Full-text

Electronic structure of the thermoelectric materials PbTe and AgPb18SbTe20 from first-principles calculations

Journal of Materials Research ◽

10.1557/jmr.2010.0145 ◽

2010 ◽

Vol 25 (6) ◽

pp. 1030-1036 ◽

Cited By ~ 4

Author(s):

Pengxian Lu ◽

Zigang Shen ◽

Xing Hu

Keyword(s):

Band Structure ◽

Thermoelectric Properties ◽

First Principles ◽

Electronic Structures ◽

Density Functional ◽

Partial Density ◽

Functional Theory ◽

The Density Functional Theory ◽

Scanning Transmission ◽

Linearized Augmented Plane Wave

To investigate the effects of substituting Ag and Sb for Pb on the thermoelectric properties of PbTe, the electronic structures of PbTe and AgPb18SbTe20 were calculated by using the linearized augmented plane wave based on the density-functional theory of the first principles. By comparing the differences in the band structure, the partial density of states (PDOS), the scanning transmission microscope, and the electron density difference for PbTe and AgPb18SbTe20, we explained the reason from the aspect of electronic structures why the thermoelectric properties of AgPb18SbTe20 could be improved significantly. Our results suggest that the excellent thermoelectric properties of AgPb18SbTe20 should be attributed in part to the narrowing of its band gap, band structure anisotropy, the much extrema and large DOS near Fermi energy, as well as the large effective mass of electrons. Moreover, the complex bonding behaviors for which the strong bonds and the weak bonds are coexisted, and the electrovalence and covalence of Pb–Te bond are mixed should also play an important role in the enhancement of the thermoelectric properties of the AgPb18SbTe20.

Download Full-text