scholarly journals First-Principles Study of Structure, Elastic Properties, and Thermal Conductivity of Monolayer Calcium Hydrobromide

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Si-Hua Li ◽  
Cui-E Hu ◽  
Xiao-Lu Wang ◽  
Yan Cheng
Keyword(s):  
Thermal Conductivity ◽  
Elastic Properties ◽  
First Principles ◽  
Lattice Thermal Conductivity ◽  
Mechanical Stability ◽  
Iterative Solution ◽  
Mean Free Path ◽  
Hydrogen Atmosphere ◽  
Theoretical Studies ◽  
Boltzmann Transport

In recent years, some laboratories have been able to prepare calcium hydrobromide (CaHBr) by melting hydride and anhydrous bromide or metal and bromide in a hydrogen atmosphere at 900°C and have studied some of its properties. But there are few theoretical studies, especially the theoretical studies of monolayer CaHBr. We use the first-principles method to calculate the structure, elastic properties, and lattice thermal conductivity of the monolayer CaHBr based on the Boltzmann transport equation. We obtain a stable crystal structure by the optimization of monolayer CaHBr. By calculating the elastic constant of monolayer CaHBr, its mechanical stability is proved, and the elastic limit of monolayer CaHBr is obtained by biaxial tensile strain on monolayer CaHBr. And the corresponding phonon spectra show no imaginary frequency, indicating the dynamic stability of the monolayer CaHBr. By the ShengBTE code, we calculate the lattice thermal conductivity of the monolayer CaHBr, the iterative solution of BTE and RTA at 300 K–1200 K is obtained, and the lattice thermal conductivity at room temperature is κ ι BTE = 2.469   W / m ⋅ K and κ ι RTA = 2.201   W / m ⋅ K , respectively. It can be seen that the lattice thermal conductivity of monolayer CaHBr is low. And by analyzing the phonon spectrum, the scattering rate, and the mean free path of the phonons, the lattice thermal conductivity of monolayer CaHBr mainly depends on the acoustic modes. We hope this study can provide theoretical guidance for the experiments and practical application of monolayer CaHBr.

scholarly journals Ultralow and anisotropic thermal conductivity in semiconductor As2Se3

2018 ◽  
Vol 20 (3) ◽  
pp. 1809-1816 ◽  
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.

Strain engineering of phonon thermal transport properties in monolayer 2H-MoTe2

2017 ◽  
Vol 19 (47) ◽  
pp. 32072-32078 ◽  
Author(s):  
Aamir Shafique ◽  
Young-Han Shin
Keyword(s):  
Thermal Conductivity ◽  
First Principles ◽  
Lattice Thermal Conductivity ◽  
Boltzmann Transport Equation ◽  
Strain Engineering ◽  
First Principles Calculations ◽  
Boltzmann Transport ◽  
Phonon Group Velocity ◽  
Phonon Lifetime ◽  
Phonon Properties

The effect of strain on the phonon properties such as phonon group velocity, phonon anharmonicity, phonon lifetime, and lattice thermal conductivity of monolayer 2H-MoTe2is studied by solving the Boltzmann transport equation based on first principles calculations.

First-Principles Study on Mn-Doped TiFeSb Half-Heusler Thermoelectric Materials

2013 ◽  
Vol 762 ◽  
pp. 471-475 ◽  
Author(s):  
Zhong Hong Lai ◽  
Jian Ma ◽  
Jing Chuan Zhu
Keyword(s):  
Thermal Conductivity ◽  
Density Of States ◽  
Thermoelectric Materials ◽  
First Principles ◽  
Lattice Thermal Conductivity ◽  
Mechanical Stability ◽  
Electronic Conductivity ◽  
Phonon Transport ◽  
Doping Amount ◽  
Mn Doped

The 8.33at% Mn-doped TiFeSb half-heusler thermoelectric materials were studied by first-principles in this paper. The space occupying of Mn atoms in Mn-doped TiFeSb system was studied according to thermodynamic stability, mechanical stability, and density of states at the Fermi level. The results show that Mn atoms would substitute Ti atoms preferentially at 8.33at% doping amount. The electronic and phonon transport properties were calculated in TiFeSb and (Ti0.75Mn0.25)FeSb to characterize their electronic and thermal conductivity. The results indicate that Mn-doping can increase the power factor due to improving the electronic conductivity while reducing the lattice thermal conductivity. Therefore, the (Ti0.75Mn0.25)FeSb are expected to show better thermoelectric properties than TiFeSb.

Disparate strain response of the thermal transport properties of bilayer penta-graphene as compared to that of monolayer penta-graphene

2019 ◽  
Vol 21 (28) ◽  
pp. 15647-15655 ◽  
Author(s):  
Zhehao Sun ◽  
Kunpeng Yuan ◽  
Xiaoliang Zhang ◽  
Guangzhao Qin ◽  
Xiaojing Gong ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Transport Equation ◽  
First Principles ◽  
Room Temperature ◽  
Lattice Thermal Conductivity ◽  
Boltzmann Transport Equation ◽  
Strain Response ◽  
First Principles Calculations ◽  
Boltzmann Transport ◽  
Strain Modulation

In this study, strain modulation of the lattice thermal conductivity of monolayer and bilayer penta-graphene (PG) at room temperature was investigated using first-principles calculations combined with the phonon Boltzmann transport equation.

Anisotropy in lattice thermal conductivity tensor of bulk hexagonal-MT2 (M = W, Mo and T = S and Se) by first principles phonon calculations

RSC Advances ◽  
2016 ◽  
Vol 6 (10) ◽  
pp. 7817-7828 ◽  
Author(s):  
Yingchun Ding ◽  
Min Chen ◽  
Bing Xiao
Keyword(s):  
Thermal Conductivity ◽  
Free Path ◽  
First Principles ◽  
Lattice Thermal Conductivity ◽  
Mean Free Path ◽  
Conductivity Tensor ◽  
Thermal Conductivity Tensor

Anisotropies in phonon mean free path and thermal conductivity as a function of temperature are calculated for 2H-MT2 structures.

scholarly journals Anisotropic intrinsic lattice thermal conductivity of phosphorene from first principles

2015 ◽  
Vol 17 (7) ◽  
pp. 4854-4858 ◽  
Author(s):  
Guangzhao Qin ◽  
Qing-Bo Yan ◽  
Zhenzhen Qin ◽  
Sheng-Ying Yue ◽  
Ming Hu ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Free Path ◽  
First Principles ◽  
Lattice Thermal Conductivity ◽  
Mean Free Path

The intrinsic lattice thermal conductivity and the representative phonon mean free path of phosphorene.

Effects of tensile strain and finite size on thermal conductivity in monolayer WSe2

2019 ◽  
Vol 21 (1) ◽  
pp. 468-477 ◽  
Author(s):  
Kunpeng Yuan ◽  
Xiaoliang Zhang ◽  
Lin Li ◽  
Dawei Tang
Keyword(s):  
Thermal Conductivity ◽  
Transport Equation ◽  
First Principles ◽  
Tensile Strain ◽  
Lattice Thermal Conductivity ◽  
Boltzmann Transport Equation ◽  
Finite Size ◽  
Boltzmann Transport ◽  
Size Dependent

The strain- and size-dependent lattice thermal conductivity of monolayer WSe2 has been investigated using the first-principles based Boltzmann transport equation.

scholarly journals Ultralow lattice thermal conductivity of chalcogenide perovskite CaZrSe3 contributes to high thermoelectric figure of merit

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Eric Osei-Agyemang ◽  
Challen Enninful Adu ◽  
Ganesh Balasubramanian
Keyword(s):  
Thermal Conductivity ◽  
Figure Of Merit ◽  
Density Functional ◽  
Lattice Thermal Conductivity ◽  
Phonon Scattering ◽  
Mean Free Path ◽  
Thermoelectric Figure Of Merit ◽  
Boltzmann Transport ◽  
Phonon Modes ◽  
Thermoelectric Figure

AbstractAn emerging chalcogenide perovskite, CaZrSe3, holds promise for energy conversion applications given its notable optical and electrical properties. However, knowledge of its thermal properties is extremely important, e.g. for potential thermoelectric applications, and has not been previously reported in detail. In this work, we examine and explain the lattice thermal transport mechanisms in CaZrSe3 using density functional theory and Boltzmann transport calculations. We find the mean relaxation time to be extremely short corroborating an enhanced phonon–phonon scattering that annihilates phonon modes, and lowers thermal conductivity. In addition, strong anharmonicity in the perovskite crystal represented by the Grüneisen parameter predictions, and low phonon number density for the acoustic modes, results in the lattice thermal conductivity to be limited to 1.17 W m−1 K−1. The average phonon mean free path in the bulk CaZrSe3 sample (N → ∞) is 138.1 nm and nanostructuring CaZrSe3 sample to ~10 nm diminishes the thermal conductivity to 0.23 W m−1 K−1. We also find that p-type doping yields higher predictions of thermoelectric figure of merit than n-type doping, and values of ZT ~0.95–1 are found for hole concentrations in the range 1016–1017 cm−3 and temperature between 600 and 700 K.

scholarly journals Anisotropic Thermal Conductivity in Few-Layer and Bulk Titanium Trisulphide from First Principles

Nanomaterials ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 704 ◽  
Author(s):  
Fernan Saiz ◽  
Jesus Carrete ◽  
Riccardo Rurali
Keyword(s):  
Thermal Conductivity ◽  
Ab Initio ◽  
Transport Equation ◽  
First Principles ◽  
Boltzmann Transport Equation ◽  
Iterative Solution ◽  
Boltzmann Transport ◽  
Fundamental Symmetries ◽  
Phonon Branch ◽  
Anisotropic Thermal Conductivity

We study the thermal conductivity of monolayer, bilayer, and bulk titanium trisulphide (TiS 3 ) by means of an iterative solution of the Boltzmann transport equation based on ab-initio force constants. Our results show that the thermal conductivity of these layers is anisotropic and highlight the importance of enforcing the fundamental symmetries in order to accurately describe the quadratic dispersion of the flexural phonon branch near the center of the Brillouin zone.

scholarly journals Effects of low dimensionality on electronic structure and thermoelectric properties of bismuth

RSC Advances ◽  
2019 ◽  
Vol 9 (69) ◽  
pp. 40670-40680 ◽  
Author(s):  
C. Y. Wu ◽  
L. Sun ◽  
J. C. Han ◽  
H. R. Gong
Keyword(s):  
Thermal Conductivity ◽  
Electronic Structure ◽  
Band Structure ◽  
First Principles ◽  
Lattice Thermal Conductivity ◽  
Transport Theory ◽  
First Principles Calculations ◽  
Boltzmann Transport ◽  
Boltzmann Transport Theory ◽  
Low Dimensionality

First-principles calculations and Boltzmann transport theory have been combined to comparatively investigate the band structure, phonon spectrum, lattice thermal conductivity, and the transport properties of the β-bismuth monolayer and bulk Bi.

Sign in / Sign up

Export Citation Format

Share Document