Article
Chemistry, Multidisciplinary
Flor Maria Briceno-Vargas, Mariana Quesadas-Rojas, Gumersindo Miron-Lopez, David Caceres-Castillo, Ruben M. Carballo, Gonzalo J. Mena-Rejon, Ramiro F. Quijano-Quinones
Summary: This study investigates the n -> pi* interactions in amides and thioamides systems models through the analysis of electron density topology. The results suggest that dispersion forces play a significant role in the strength of these interactions.
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
Materials Science, Multidisciplinary
Zhenyu Hu, Dan Zhao, Yuheng Li, Xin Lv, Jinhui Song, Lingyi Meng, Shui-yang Lien, Peng Gao
Summary: The demand for sustainable power supply and management has increased with the rise of IoT devices. In this study, we tackled the low electrical conductivity issue of Bi2S3 thin films by incorporating Cl into the lattice. The doping of Cl led to an increase in conductivity and carrier concentration, making Bi2S3 a promising solution for low-cost power supply in IoT applications.
ACS MATERIALS LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Aksel Kobialka, Malgorzata Sternik, Andrzej Ptok
Summary: This article discusses the lattice dynamics and mode activity of recently discovered magnetic topological insulators TBi2Te4 (T = Mn, Fe). The results confirm the dynamical stability of these compounds in a specific phase and analyze the frequencies of Raman active modes.
Article
Materials Science, Multidisciplinary
Bruno Focassio, Gabriel R. Schleder, Marcio Costa, Adalberto Fazzio, Caio Lewenkopf
Summary: The study reveals that the two-dimensional amorphous bismuthene structures are topological insulators, with the stability of the topological phase being correlated with the strength of spin-orbit coupling and the size of the original topological gap. In terms of electronic transport properties, a conductance plateau of 2e(2)/h is found within the topological gap, along with Anderson localization onset in the trivial insulator phase.
Article
Nanoscience & Nanotechnology
Thomas K. Reid, Baris Yavas, Sanjubala Sahoo, S. Pamir Alpay
Summary: Aluminum-silicon is a binary eutectic system where the solid solubility of aluminum in silicon is limited. The addition of alkaline earth elements to the eutectic phase mixture of Al-Si leads to a change in morphology from planar to three-dimensional with facets on (111) planes. In this study, first-principles calculations are used to explain the origin of these morphological variations and the influence of interatomic interactions between aluminum, silicon, and inoculant atoms.
SCRIPTA MATERIALIA
(2023)
Article
Physics, Multidisciplinary
Rui Tan, Qirui Yang, Ruiyuan Chen, Yu Qiao, Shouqiao Tan, Yanqiang Cao, Peng Wang, Tai-Chang Chiang, Xiaoxiong Wang
Summary: We use first-principles simulation and alchemical mixing approximation to reveal the unique double band inversion and topological phase transition in Ge1-xSnx alloys. The band inversion in Ge1-xSnx is relayed by its first valence band, and as the system evolves from Ge to alpha-Sn, its conduction band moves down, inverting with the first and second valence bands consecutively. The first band inversion makes the system nontrivial, while the second one does not change the system's topological invariant. Both band inversions yield surface modes spanning the individual inverted gaps, but only the surface mode in the upper gap associates with the nontrivial nature of tensile-strained alpha-Sn.
Article
Chemistry, Multidisciplinary
Nuno M. Fortunato, Andreas Taubel, Alberto Marmodoro, Lukas Pfeuffer, Ingo Ophale, Hebert Ebert, Oliver Gutfleisch, Hongbin Zhang
Summary: Magnetic refrigeration is an efficient and eco-friendly alternative to traditional vapor-cooling, but its implementation relies on materials with tailored magnetic and structural properties. This study introduces a high-throughput computational workflow for designing magnetocaloric materials, using density functional theory calculations to screen potential candidates in the MM'X compound family (M/M' = metal, X = main group element). Out of 274 stable compositions, 46 magnetic compounds are found to stabilize in both austenite and martensite phases. By evaluating and comparing the structural phase transition and magnetic ordering temperatures, nine compounds with structural transitions are identified as potential candidates based on the concept of the Curie temperature window. Additionally, the use of doping to tailor magnetostructural coupling and isostructural substitution as a general approach to engineer magnetocaloric materials is suggested.
Article
Chemistry, Multidisciplinary
Y. Ammari, E. K. Hlil
Summary: In this study, the structural, electronic, and optical properties of nitride ternary phase CaNiN containing nickel (I) and calcium were investigated using density functional theory. It was found that the non-spin polarized state is more stable, and Dirac-cones-like band crossings were observed in the band structure. The study also utilized many-body perturbation theory to analyze optical properties of the compound.
Article
Physics, Condensed Matter
A. N. Filanovich, A. V. Lukoyanov, A. A. Povznera
Summary: Double half Heusler alloys are promising materials for thermoelectric power converters. In this study, the lattice thermal conductivity of 118 such alloys was predicted using machine learning, and five compositions with the lowest thermal conductivity were identified. The electronic and elastic properties of these alloys were then studied, and it was found that three of them have a small band gap width, indicating excellent electronic thermoelectric properties. Additionally, the analysis of the elastic characteristics showed that these alloys are ductile and have low anisotropy of the elastic properties.
PHYSICA B-CONDENSED MATTER
(2023)
Article
Nanoscience & Nanotechnology
Yuki Yoshimoto, Takahiro Toma, Kenta Hongo, Kousuke Nakano, Ryo Maezono
Summary: The cathode material of a lithium-ion battery plays a crucial role in the durability, capacity, and safety of the battery. LiNiO2 has attracted attention as a potential cathode material for higher capacity due to its ability to extract more lithium at the same voltage compared to LiCoO2. However, it is prone to pyrolysis, which can lead to ignition and explosion hazards. This study investigates possible elemental substitutions to suppress pyrolysis and identifies P, Ta, and W as promising solutions.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
T. Kana, J. Cermak, L. Kral
Summary: Ab initio calculations were performed on Mg2Ni compound and its hydride Mg2NiH4 doped with elements X = Al, Ga, In, Si, Ge, and Sn, showing a reduction in hydrogen desorption enthalpy for both concentrations of X. Doping with In at low concentration weakened Ni-H bonds in Mg-2(Ni-In)H-4 hydride while enhancing bonding between Mg and H atoms. These findings provide valuable insights into enhancing hydrogen storage properties in metal hydride systems.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Materials Science, Multidisciplinary
Pablo Aguado-Puente, Piotr Chudzinski
Summary: This study investigates whether the topologically nontrivial properties of topological insulators survive at finite temperatures and examines the temperature at which they disappear. By using quantum fidelity and an effective dissipative theory, the researchers reveal a characteristic temperature, lower than the gap-closing one, indicating a loss of coherence of the topological state in SnTe, a prototype crystal topological insulator. The transition is only present when a dissipative bosonic bath is coupled.
Article
Engineering, Electrical & Electronic
F. Djali, T. Ouahrani, S. Hiadsi, M. R. Boufatah
Summary: This study presents the first attempt to investigate the thermoelectric properties of FeZrTe half-Heusler alloy through theoretical calculations. The phonon dispersion and crystal structures are obtained using density functional theory and finite displacement method. The results show that FeZrTe alloy is mechanically and dynamically stable in its type I structure, and has a semiconducting character with a band gap of 1.4 eV. The variations of thermoelectric properties with carrier concentration and temperature have been studied, indicating the potential for constructing an n-p couple for a thermoelectric device.
JOURNAL OF ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Feng-Xian Bai, Hao Yu, Ya-Kang Peng, Shan Li, Li Yin, Ge Huang, Liu-Cheng Chen, Alexander F. Goncharov, Jie-He Sui, Feng Cao, Jun Mao, Qian Zhang, Xiao-Jia Chen
Summary: This study found that the electrical properties of Bi0.5Sb1.5Te3 can be effectively improved by applying external pressure through inducing an electronic topological transition, resulting in a higher figure of merit at room temperature.
