A5100326394- Thermal properties of materials
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Advanced Thermoelectric Materials and Devices
- Graphene research and applications
- 2D Materials and Applications
- Thermal Radiation and Cooling Technologies
- Economic theories and models
- Advanced Optimization Algorithms Research
- Machine Learning in Materials Science
- Crystallography and molecular interactions
- Aluminum Alloy Microstructure Properties
- Optimization and Variational Analysis
- Boron and Carbon Nanomaterials Research
- MXene and MAX Phase Materials
- Aluminum Alloys Composites Properties
- Semiconductor materials and devices
- Metal and Thin Film Mechanics
- Research in Cotton Cultivation
- Economic Theory and Policy
- Electron and X-Ray Spectroscopy Techniques
- High-pressure geophysics and materials
- Advanced Materials Characterization Techniques
- Advanced Electron Microscopy Techniques and Applications
- Advancements in Semiconductor Devices and Circuit Design
Hunan University of Traditional Chinese Medicine
2024-2025
Shenzhen University
2016-2024
Eastern Institute of Technology, Ningbo
2023-2024
Yunnan University
2023
Shandong Lianxing Energy Group (China)
2022
Jiangsu University of Science and Technology
2020-2022
Shenyang Ligong University
2021
China Ocean Shipping (China)
2021
China University of Geosciences (Beijing)
2021
South China Institute of Collaborative Innovation
2019-2020
The lattice thermal conductivity ($\ensuremath{\kappa}$) of the thermoelectric materials, Mg${}_{2}$Si, Mg${}_{2}$Sn, and their alloys, are calculated for bulk nanowires, without adjustable parameters. We find good agreement with experimental results. For large nanowire diameters, size effects stronger alloy than pure compounds. example, in 200 nm diameter nanowires $\ensuremath{\kappa}$ is lower its value by 30$%$, 20$%$, 20$%$ Mg${}_{2}$Si${}_{0.6}$Sn${}_{0.4}$, respectively. less 20...
Experimentally determining the lattice thermal conductivity of materials with very high or low values is expensive and time consuming. An efficient computational approach using machine-learning techniques finds a much larger range than expected for an impressive number half-Heusler compounds also offers way to rapidly evaluate other classes materials.
A rigorous first principles Boltzmann-Peierls equation (BPE) for phonon transport approach is employed to examine the lattice thermal conductivity, ${\ensuremath{\kappa}}_{L}$, of strained and unstrained graphene. First calculations show that out-of-plane, flexural acoustic phonons provide dominant contribution ${\ensuremath{\kappa}}_{L}$ graphene all strains, temperatures, system sizes considered, supporting a previous prediction used an optimized Tersoff empirical interatomic potential....
Using ab initio calculations we have investigated the thermal conductivity ($\ensuremath{\kappa}$) of diamond nanowires, unveiling unusual features unique to this system. In sharp contrast with Si, $\ensuremath{\kappa}(T)$ nanowires as thick 400 nm still increase monotonically temperature up 300 K, and room-temperature size effects are stronger than for Si. A marked dependence $\ensuremath{\kappa}$ on crystallographic orientation is predicted, which apparent even at room temperature. [001]...
Using ab initio calculations, we have investigated the phonon linewidths and thermal conductivity (κ) of monolayer MoS2. κ for a typical sample size 1 μm is 83 W/m K at room temperature in completely rough edge limit, suggesting not limiting factor electronic application can be further increased by 30% 10 sized samples. Due to strong anharmonicity, isotope enhancement only 10% However, significantly reduced, instance, Raman active modes A1g E2g1, isotopically pure
An increasing number of theoretical calculations on few-layer materials have been reporting a non-zero sound velocity for all three acoustic phonon modes. In contrast with these reports, here we show that the lowest dispersion branch atomistically described should be quadratic, and this can dramatic consequencies calculated properties, such as thermal conductivity. By reformulating interatomic force constants (IFC) in terms internal coordinates, find delicate balance between IFCs is...
We study the lattice thermal conductivity $(\ensuremath{\kappa})$ of fully filled skutterudites $\mathrm{YbFe}{}_{4}{\text{Sb}}_{12}$ and ${\text{BaFe}}_{4}{\text{Sb}}_{12}$ from first principles. The calculated $\ensuremath{\kappa}$ ${\text{YbFe}}_{4}{\text{Sb}}_{12}$ is ten times lower than that for $\mathrm{BaFe}{}_{4}{\text{Sb}}_{12}$, much any values ever reported other skutterudites. ultralow closely related to flat Yb-dominated modes appearing in frequency range 5 7.2 rad/ps....
We demonstrate the ab initio electrical transport calculation limited by electron-phonon coupling using full solution of Boltzmann equation (BTE), which applies equally to metals and semiconductors. Numerical issues are emphasized in this work. show that simple linear interpolation matrix elements from a relatively coarse grid an extremely fine can ease calculational burden, makes feasible practice. For Brillouin zone (BZ) integration transition probabilities involving one...
Functionalized MXenes hold promises in a variety of applications which the dispensable functional groups are mixed. The functionalization is spontaneously realized through competitive adsorption active species on MX matrix during acid etching process MAX phases. Nevertheless, knowledge proportion and distribution MXenes, i.e., surface structures, still limited. By high-throughput computation screening, ground-state stable structures four kinds typical MXenes—Ti2CTx, Ti3C2Tx, Nb2CTx, Nb4C3Tx...
Using ab initio calculations we have investigated the lattice thermal conductivity ($\ensuremath{\kappa}$) of ${\mathrm{CoSb}}_{3}$ and ${\mathrm{BaCo}}_{4}$${\mathrm{Sb}}_{12}$. The calculated room temperature $\ensuremath{\kappa}$ these compounds are 11.5 6.1 W/m K, respectively. change in upon filling is mainly due to reduction phonon lifetimes limited by anharmonic scattering, which occurs whole spectrum, ruling out postulated ``rattling'' model. We show that harmonic interaction instead...
With first-principles calculated electron-phonon coupling matrix elements, the phonon-limited electron and hole mobilities of Si GaAs are studied using Boltzmann transport equation. The agree well with experimental measurements. For electrons in GaAs, mobility is very sensitive to band structure characterized by effective mass energy gap between $\mathrm{\ensuremath{\Gamma}}$ L valleys, which clarifies discrepancies recent literature findings [J.-J. Zhou M. Bernardi, Phys. Rev. B 94,...
It has been highly debated whether the thermal conductivity κ of a disordered SiGe alloy can be lowered by redistributing its constituent species so as to form an ordered superlattice. By ab initio calculations backed systematic experiments, we show that Ge segregation occurring during epitaxial growth lead values not only lower than alloy's, but also perfect superlattice values. Thus theoretically demonstrate does monotonically decrease Si- and Ge-rich regions become more sharply defined....
We show that impurities and vacancies affect the thermal conductivity much more strongly than what is predicted by widely accepted models. When local distortions around point defects are strong, standard perturbative approaches fail, phonon scattering can only be accounted for an exact Green's function calculation. apply theory to study, from first-principles, of nitrogen vacancy in diamond. The computed solving linearized Boltzmann transport equation. Born approximation underestimates cross...
Within the past few years, tin selenide (SnSe) has attracted intense interest due to its remarkable thermoelectric potential for both $n$- and $p$-type crystals. In this work, intrinsic phonon-limited electron/hole mobilities of SnSe are investigated using a Boltzmann transport equation based on first-principles calculated electron-phonon interactions. We find that electrons have much larger than holes. At room temperature, along $a$, $b$, $c$ axes 325, 801, 623 ${\mathrm{cm}}^{2}$/V s,...
Highly thermally conductive, electrically insulating, and flexible nanocellulose composite films are crucially significant for the thermal management of next-generation green electronics. However, intrinsic hygroscopicity poses a daunting challenge to reliability structural stability electronic products. To address these issues, herein, dual bio-inspired design was innovatively introduced fabricate highly conductive superhydrophobic nanocellulose-based via vacuum-assisted self-assembly...
Tungsten is known to have a Lorenz number $L$ larger than the Sommerfeld value (${L}_{0}={\ensuremath{\pi}}^{2}{k}_{B}^{2}/3{e}^{2}=2.445\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}8}\phantom{\rule{0.16em}{0ex}}{\mathtt{V}}^{2}/{\mathtt{deg}}^{2}$) by 30%. By performing fully first-principles calculations, we are able calculate electrical conductivity ($\ensuremath{\sigma}$) and quantify electronic (${\ensuremath{\kappa}}_{e}$) lattice (${\ensuremath{\kappa}}_{\mathtt{ph}}$)...
Extracting long-lasting performance from electronic devices and improving their reliability through effective heat management requires good thermal conductors. Taking both three- four-phonon scattering as well electron-phonon isotope into account, we predict that semimetallic $\ensuremath{\theta}$-phase tantalum nitride ($\ensuremath{\theta}\text{\ensuremath{-}}\mathrm{TaN}$) has an ultrahigh conductivity ($\ensuremath{\kappa}$), of 995 $\text{820 }\mathrm{W}\text{...
The recycled concrete fine powder (RFP) after calcination activation not only contains active with potential hydration characteristics, but also may cause the limestone contained in to form calcium oxide. effects of TRFP-750 and TRFP-850(RFP calcined at 750 ℃ 850 ℃) replacing oxide on preparation properties autoclaved aerated (AAC) were investigated this study. results showed that when 60% quicklime is replaced by TRFP-850, AAC strength greater than 2.5 MPa density less 550 kg/m3 can be...
Recent theoretical and experimental research suggests that $\ensuremath{\theta}$-TaN is a semimetal with high thermal conductivity ($\ensuremath{\kappa}$), primarily due to the contribution of phonons (${\ensuremath{\kappa}}_{\mathsf{ph}}$). By using first-principles calculations, we show nonmonotonic pressure dependence $\ensuremath{\kappa}$ $\ensuremath{\theta}$-TaN. ${\ensuremath{\kappa}}_{\mathsf{ph}}$ first increases until it reaches maximum at around 60 GPa, then decreases. This...
We propose a possible route to achieve high thermoelectric efficiency in molecular junctions by combining local chemical tuning of the electronic states with use semiconducting electrodes. The former allows control position highest-occupied orbital (HOMO) transmission resonance respect Fermi energy while latter fulfills twofold purpose: suppression electronlike contributions thermopower and cutoff HOMO tails into semiconductor band gap. As result large can be obtained. Our results strongly...