Article
Chemistry, Physical
Xin Liu, Dingbo Zhang, Hui Wang, Yuanzheng Chen, Hongyan Wang, Yuxiang Ni
Summary: The CaAs3 monolayer exhibits low lattice thermal conductivity, high Seebeck coefficient, and electrical conductivity, making it a promising candidate for applications in the thermoelectric field. Compared with conventional 2D thermoelectric materials, it does not contain expensive heavy elements, which is advantageous for practical applications as a thermoelectric material.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Bingke Li, Chenghua Zhang, Zhehao Sun, Tao Han, Xiang Zhang, Jia Du, Jiexue Wang, Xiuchan Xiao, Ning Wang
Summary: This study uses first-principles calculations to investigate the thermoelectric properties of Tl3XSe4. The results show that Tl3XSe4 exhibits excellent thermoelectric performance, making it a potential high-performance thermoelectric material.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Physics, Applied
Yongchao Rao, C. Y. Zhao, Shenghong Ju
Summary: In this study, the thermal and electrical transport properties of diamond-cubic and metastable R8 phases of Si are comparatively studied. The results show that the metastable Si has lower lattice thermal conductivity and excellent electrical conductivity, leading to higher thermoelectric performance in n-type doping.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
Jinfeng Yang, Zhaoyu Yang, Xiaonan Wang, Yuxiang Chen, Yongze Xu, Bo Zou, Yuli Yan, Huarui Sun
Summary: In this study, Zintl-phase TiNiSi-type SrMgSi and CaMgGe with low intrinsic lattice thermal conductivity were investigated for thermoelectric applications. The low thermal conductivity is attributed to the strong lattice anharmonicity and optical-acoustic phonon coupling, while the high band degeneracy leads to good electrical properties. The predicted ZT values for SrMgSi and CaMgGe were 2.83 and 3.09, respectively.
ACS APPLIED ENERGY MATERIALS
(2023)
Article
Physics, Condensed Matter
Maryam Rouzbehi, Ali Kazempour, Aliasghar Shokri, Leila Gholamzadeh
Summary: The study explores the impact of doping on the transport properties of HfH2. It is found that at low doping levels, both electrical and thermal conductivities increase with electron carrier concentrations, while irregular behavior is observed in the hole carrier concentration regime. Additionally, the results indicate that hole doping is more effective in achieving lower electron thermal conductivity in comparison to pure HfH2.
PHYSICA B-CONDENSED MATTER
(2021)
Article
Chemistry, Inorganic & Nuclear
Niharendu Barman, Arabinda Barman, Prabir Kumar Haldar
Summary: In this study, computational methods were used to evaluate the thermoelectric properties of KBaBi, revealing promising ZT values especially for p-type conductivity along the c-axis. KBaBi demonstrates potential for high thermoelectric performance, particularly in terms of electrical conductivity along the c-axis.
JOURNAL OF SOLID STATE CHEMISTRY
(2021)
Article
Crystallography
Naoki Sato, Yoshiki Takagiwa
Summary: By conducting first-principles calculations, the microscopic mechanism of thermal transport in Fe3Al2Si3 was clarified, and effective strategies to reduce lattice thermal conductivity were established. It was found that heavy-element doping on the Al site and controlling the fine microstructure are effective ways to decrease lattice thermal conductivity, providing valuable information for practical applications of this material.
Article
Chemistry, Multidisciplinary
Enamul Haque, Mizanur Rahaman
Summary: This study investigated the structural stability and thermoelectric properties of the earth-abundant and non-toxic SrGaSnH material using density functional theory, density functional perturbation theory, and semiclassical Boltzmann transport theory. The compound showed good structural stability, with an indirect bandgap semiconductor property. While it exhibited high electrical conductivity along the x-axis, the presence of weak phonon scattering resulted in high lattice thermal conductivity, limiting the ZT value. Despite this, the compound showed strong potential for eco-friendly thermoelectric applications.
Article
Nanoscience & Nanotechnology
Himanshu Nautiyal, Paolo Scardi
Summary: Tin-based chalcogenides, especially the hexagonal Janus SnSSe monolayer, show potential as high-performing thermoelectric materials with ultra-low thermal conductivity and superior zT values under p-type doping condition.
Article
Chemistry, Physical
Sree Sourav Das, Md. Golam Rosul, Mona Zebarjadi
Summary: We propose a first-principles framework to study the electronic properties of SnSe2 and optimize its thermoelectric performance. By using density functional theory and the Boltzmann transport equation, we calculate the thermoelectric power factor considering electron-phonon and ionized impurity interactions. Furthermore, we evaluate the lattice thermal conductivity and find that the SnSe2 layers exhibit ultra-low thermal conductivity, resulting in a high ZT value of 1.1 at 950 K.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Zhi Li, Hongyao Xie, Yi Xia, Shiqiang Hao, Koushik Pal, Mercouri G. Kanatzidis, Christopher Wolverton, Xinfeng Tang
Summary: By introducing weak-bonding elements Ba or Sr into the SnS2 framework, two SnS2-based materials BaSnS3 and SrSnS3 with low thermal conductivity and high carrier mobility were discovered, showing potential for high-performance thermoelectric applications.
CHEMISTRY OF MATERIALS
(2022)
Article
Physics, Condensed Matter
Neelesh Gupta, Rekha Verma
Summary: This study investigates the thermoelectric transport coefficients in silicene using first-principles calculations, finding that the lattice thermal conductivity of intrinsic monolayer silicene is relatively high and the figure-of-merit in n-type material is better than that of p-type. Comparing the results obtained with HSE06 hybrid functional and PBE functional shows a significant improvement in the values of the transport coefficients calculated using HSE06.
PHYSICA B-CONDENSED MATTER
(2021)
Article
Chemistry, Physical
Bingke Li, Yongsheng Yang, Zhehao Sun, Hangbo Qi, Zhihui Xiong, Keliang Wu, Huanxin Li, Kenan Sun, Xiuchan Xiao, Chen Shen, Ning Wang
Summary: Novel thermoelectric materials have been rapidly screened out through high-throughput calculation, although further accurate analysis is needed to understand their microscopic transport mechanism. Monolayer Hf2Cl4 shows excellent TE performance with highly anisotropic TE parameters, making it a potential candidate for TE materials. High-throughput calculation screening is effective in enhancing TE performance.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Physics, Condensed Matter
Min Liu, Shao-Bo Chen, Cui-E Hu, Yan Cheng, Hua-Yun Geng
Summary: In this study, we systematically reported the properties of the AsSBr monolayer, including its electronic structure, lattice thermal conductivity, thermal transport properties, and thermoelectricity. The results showed that the AsSBr monolayer is a dynamically stable indirect bandgap semiconductor with a low lattice thermal conductivity. It was also found that the p-type AsSBr monolayer exhibits excellent thermoelectric performance at high temperatures.
SOLID STATE COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Ning Wang, Menglu Li, Haiyan Xiao, Zhibin Gao, Zijiang Liu, Xiaotao Zu, Sean Li, Liang Qiao
Summary: Band degeneracy is effective in optimizing the power factors of thermoelectric materials, with n-type systems showing better TE performance in LaCuOSe and BiCuOSe due to longer electron relaxation times.
NPJ COMPUTATIONAL MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Xinyi He, Seiya Nomoto, Takehito Komatsu, Takayoshi Katase, Terumasa Tadano, Suguru Kitani, Hideto Yoshida, Takafumi Yamamoto, Hiroshi Mizoguchi, Keisuke Ide, Hidenori Hiramatsu, Hitoshi Kawaji, Hideo Hosono, Toshio Kamiya
Summary: A new approach using hydride anion (H-) substitution for oxide ion is proposed to enhance the ZT value of thermoelectric oxide SrTiO3, achieving environmentally friendly and high-energy conversion efficiency.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Physics, Applied
Amran Mahfudh Yatmeidhy, Yoshihiro Gohda
Summary: We investigate the microscopic origin of strain-induced changes in the magnetocrystalline anisotropy energy of Co2FeSi, Co2MnSi, and Fe3Si Heusler alloys using first-principles electron theory. The anisotropy modulation in Co2FeSi and Co2MnSi is dominated by the quadrupole moment of Co minority-spin states under strain within the (001) plane, leading to giant magnetoelectric couplings in multiferroic heterointerfaces containing these compounds. On the other hand, the strain-induced anisotropy modulation in Fe3Si has mixed contributing factors including the anisotropy term of the orbital magnetic moment and the quadrupole term.
APPLIED PHYSICS EXPRESS
(2023)
Article
Chemistry, Physical
Dhruba B. Khadka, Yasuhiro Shirai, Masatoshi Yanagida, Terumasa Tadano, Kenjiro Miyano
Summary: In this study, formohydrazide (FHZ) was introduced as a bidentate ligand to improve the optoelectronic properties of Sn-halide perovskite solar cells (Sn-PSCs). The FHZ additive effectively suppressed Sn-oxidation and modulated the energy band structure. Device efficiency increased to 12.87% with enhanced open circuit voltage and improved device stability. The results support the importance of multidentate ligands for modulating film morphology and defect chemistry in Sn-perovskite materials.
CHEMISTRY OF MATERIALS
(2023)
Article
Physics, Applied
Soma Nishino, Yoshihiro Gohda
Summary: The stable crystal structures of SmFe12-based permanent magnets, which are expected to have crystalline grain-boundary subphases, are examined by first-principles thermodynamics. A free-energy landscape of ternary Sm-Cu-Fe is constructed, overcoming the dynamical instability problem, to identify stable crystal structures dependent on temperatures and compositions. Cu-rich B2 Sm-Cu is substantially stabilized by both phonons and configurational entropy, and Fe atoms in the Cu sublattice of B27 SmCu contribute to the phase stabilization. These findings expand the stable composition region of nonmagnetic SmCu-based intermetallics by revealing the existence of B2-B27 two-phase equilibria.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2023)
Article
Physics, Applied
Shunsuke Tsuna, Yoshihiro Gohda
Summary: First-principles investigations reveal that the presence of B in neodymium-magnet compounds leads to acoustic phonon hardening. Substituting B with other light elements results in a decrease in phonon frequencies with increasing atomic number. However, imaginary phonons in Nd2Fe14F are attributed to electronic states and atomic configurations, rather than the heavier mass of F. Additionally, the study shows that magnetic disordering reduces the softening of phonons in paramagnetic Nd2Fe14B compared to ferromagnetic Nd2Fe14B, suggesting that phonon effects decrease the Curie temperature by stabilizing the paramagnetic state.
JOURNAL OF APPLIED PHYSICS
(2023)
Review
Physics, Condensed Matter
Atsushi Togo, Laurent Chaput, Terumasa Tadano, Isao Tanaka
Summary: Scientific simulation codes, such as phonopy and phono3py, are open-source and accessible to anyone with internet connection, allowing global participation. This review presents a range of computational methods and techniques implemented in these codes, aiming to benefit the community. The techniques described here transcend phonon calculations and have potential applications in condensed matter physics.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Materials Science, Multidisciplinary
Chen Shen, Mian Dai, Xingxing Xiao, Niloofar Hadaeghi, Wenjie Xie, Anke Weidenkaff, Terumasa Tadano, Hongbin Zhang
Summary: We investigate the role of quartic anharmonicity in lattice dynamics and thermal transport of cubic EuTiO3 using ab initio self-consistent phonon theory, compressive sensing techniques, and experimental thermal conductivity measurement. We find that the strong quartic anharmonicity of oxygen atoms plays an important role in phonon quasiparticles free from imaginary frequencies in EuTiO3 and causes the hardening of vibrational frequencies of soft modes. The calculated thermal conductivity of 8.2 W/mK at 300 K matched the experimental value of 6.1 W/mK, and considering boundary scattering improved the agreement with the experiment to 6.9 W/mK at 300 K.
MATERIALS TODAY PHYSICS
(2023)
Article
Chemistry, Physical
Zhongxu Hu, Mari Hiramatsu, Xinyi He, Takayoshi Katase, Terumasa Tadano, Keisuke Ide, Hidenori Hiramatsu, Hideo Hosono, Toshio Kamiya
Summary: We demonstrated a reversible 2D-3D crystal structure transition and thermal conductivity switching in (Sn1-xPbx)S bulk polycrystals. The direct phase boundary between the 2D and 3D structures does not exist under thermal equilibrium conditions, but by using a non-equilibrium synthesis process, the phase boundary can be formed. This transition has potential applications in developing thermal management materials.
ACS APPLIED ENERGY MATERIALS
(2023)
Article
Chemistry, Physical
Satoru Enomoto, Sonju Kou, Taichi Abe, Yoshihiro Gohda
Summary: Computational examination of the phase equilibria in the Sm-Fe-Cu ternary system reveals the possibility of liquid-phase sintering producing nonmagnetic grain-boundary subphases in SmFe12-based magnets. The B2 Sm-Cu-Fe is identified as a potential nonmagnetic subphase, with attractive Cu-Fe interaction observed within the B2 sublattice. The equilibrium between the liquid phase of Sm-Cu and SmFe12 is also verified. The findings provide insights into the electron theory and suggest a feasible approach for liquid-phase sintering of SmFe12-based magnets.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Yusuke Kozuka, Taisuke T. Sasaki, Terumasa Tadano, Jun Fujioka
Summary: In this study, the fabrication and transport properties of SrPd3O4 and CaPd3O4 thin films as candidates of oxide Dirac semimetals are investigated. The observed weak temperature dependence suggests narrow-gap properties, but unintentionally doped holes hinder the discovery of the Dirac band. The study establishes the basic thermodynamics of thin-film fabrication and paves the way for exploring interesting properties of topological band structures.
SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Kouta Kazama, Masato Sakano, Kohei Yamagami, Takuo Ohkochi, Kyoko Ishizaka, Terumasa Tadano, Yusuke Kozuka, Hidetoshi Yoshizawa, Yoshihiro Tsujimoto, Kazunari Yamaura, Jun Fujioka
Summary: We investigated the charge transport property, thermoelectric effect, and electronic state of the electron-doped narrow gap semiconductor Ca1-xLaxPd3O4 through transport measurement, optical/photoemission spectroscopy, and ab initio calculation. The high-quality polycrystalline samples of Ca1-xLaxPd3O4 were synthesized using the high-pressure synthesis technique. Electron doping significantly reduced the resistivity and resulted in a metallic state at a small doping level. The power factor in the present material was much higher than that of the hole-doped analog of CaPd3O4, likely due to the relatively low resistivity and high electron mobility from the dispersive Pd 4d(x2-y2) conduction band.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Physics, Multidisciplinary
Erik Fransson, Petter Rosander, Fredrik Eriksson, J. Magnus Rahm, Terumasa Tadano, Paul Erhart
Summary: The authors discuss the overdamped limit in halide perovskites and propose an alternative model that challenges the commonly assumed temperature range. Soft modes associated with continuous-order phase transitions exhibit strong anharmonicity, leading to the breakdown of the phonon quasi-particle picture. However, the overdamped limit is typically limited to a narrow temperature range, making it difficult to observe its signature feature.
COMMUNICATIONS PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Ryota Masuki, Takuya Nomoto, Ryotaro Arita, Terumasa Tadano
Summary: We propose a theory and calculation scheme for structural optimization at finite temperatures, based on the quasiharmonic approximation (QHA). The theory includes an efficient method for updating the interatomic force constants (IFCs) called IFC renormalization. Both cell shape and atomic coordinates are simultaneously optimized. We apply this theory to study the thermal expansion and pyroelectricity of GaN and ZnO, successfully reproducing experimental observations. We also present a general scheme to obtain accurate temperature dependence with constrained optimizations, reducing the number of effective degrees of freedom.
Article
Materials Science, Multidisciplinary
Tomohito Amano, Tamio Yamazaki, Ryosuke Akashi, Terumasa Tadano, Shinji Tsuneyuki
Summary: We calculate the lattice dielectric function of strongly anharmonic rutile TiO2 using ab initio anharmonic lattice dynamics methods. By accurately calculating the I' point phonons, we show that the self-consistent approach including third-order and fourth-order anharmonicity provides better agreement with experimental measurements than a perturbative approach. Our results demonstrate the contribution of four-phonon scattering and the identification of unidentified peaks in the dielectric function as two-phonon processes. This work highlights the importance of the self-consistent approach in predicting optical properties of highly anharmonic materials.
Article
Chemistry, Physical
Zhongxu Hu, Mari Hiramatsu, Xinyi He, Takayoshi Katase, Terumasa Tadano, Keisuke Ide, Hidenori Hiramatsu, Hideo Hosono, Toshio Kamiya
Summary: We demonstrated a reversible 2D to 3D crystal structure transition and thermal conductivity switching in (Sn1-xPbx)S bulk polycrystals above room temperature. By applying a non-equilibrium synthesis process, we formed a direct phase boundary between the 2D and 3D structures in the Pb-rich (Sn0.2Pb0.8)S, which showed a reversible 2D-3D structural phase transition at around 573 K. This transition temperature is much higher than previously reported and has the potential to accelerate the development of thermal management materials.
ACS APPLIED ENERGY MATERIALS
(2023)
