arXiv 1409.21892014-09-12cond-mat.mtrl-scicond-mat.supr-con

Enhancement of thermoelectric properties by Se substitution in layered bismuth-chalcogenide LaOBiS2-xSex

Yoshikazu Mizuguchi, Atsushi Omachi, Yosuke Goto, Yoichi Kamihara, Masanori Matoba, Takafumi Hiroi, Joe Kajitani, Osuke Miura

备注：: 13 pages, 3 figs
发表信息：: J. Appl. Phys. 116, 163915 (2014)
DOI：: 10.1063/1.4900953

阅读 PDF ↗

arXiv 页面 ↗HTML 原文 ↗

英文摘要相关论文

英文摘要：

We have investigated the thermoelectric properties of the novel layered bismuth chalcogenides LaOBiS2-xSex. The partial substitution of S by Se produced the enhancement of electrical conductivity (metallic characteristics) in LaOBiS2-xSex. The power factor largely increased with increasing Se concentration. The highest power factor was 4.5 uW/cmK2 at around 470 deg. C for LaOBiS1.2Se0.8. The obtained dimensionless figure-of-merit (ZT) was 0.17 at around 470 deg. C in LaOBiS1.2Se0.8.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

阅读原文

阅读 PDF ↗

arXiv 页面 ↗HTML 原文 ↗

本文内容

英文摘要相关论文

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

继续探索

相关论文

Enhanced thermoelectricity by controlled local structure in bismuth-chalcogenides

Spectroscopic techniques, including photoelectron spectroscopy, diffuse reflectance, and x-ray absorption, are used to investigate the electronic structure and the local structure of LaOBiS$_{2-x}$Se$_x$ thermoelectric material. It is found that Se substitution effectively suppresses local distortion, that can be responsible for the increased carrier mobility together with a change in the electronic structure. The results suggest a possible way to control thermoelectric properties by tuning of the local crystal structure of these materials.

2019-03-28cond-mat.mtrl-sci

Low temperature Hall effect in bismuth chalcogenides thin films

Bismuth chalcogenides are the most studied 3D topological insulators. As a rule, at low temperatures thin films of these materials demonstrate positive magnetoresistance due to weak antilocalization. Weak antilocalization should lead to resistivity decrease at low temperatures; in experiments, however, resistivity grows as temperature decreases. From transport measurements for several thin films (with various carrier density, thickness, and carrier mobility), and by using purely phenomenological approach, with no microscopic theory, we show that the low temperature growth of the resistivity is…

2016-12-22cond-mat.mes-hallcond-mat.mtrl-sci

Dirac fermions at high-index surfaces of bismuth chalcogenide topological insulator nanostructures

Binary bismuth chalcogenides Bi$_2$Se$_3$, Bi$_2$Te$_3$, and related materials are currently being extensively investigated as the reference topological insulators (TIs) due to their simple surface-state band dispersion (single Dirac cone) and relatively large bulk band gaps. Nanostructures of TIs are of particular interest as an increased surface-to-volume ratio enhances the contribution of surfaces states, meaning they are promising candidates for potential device applications. So far, the vast majority of research efforts have focused on the low-energy (0001) surfaces, which correspond to n…

2016-06-20cond-mat.mes-hallcond-mat.mtrl-sci

Spin-lattice relaxation in bismuth chalcogenides

Bismuth chalcogenides Bi$_2$Se$_3$ and Bi$_2$Te$_3$ are semiconductors, which can be both thermoelectric materials (TE) and topological insulators (TI). Lattice defects arising from vacancies, impurities, or dopants in these materials are important in that they provide the charge carriers in TE applications and compromise the performance of these materials as TIs. We present the first solid-state nuclear magnetic resonance (NMR) study of the $^{77}$Se and $^{125}$Te NMR resonances in polycrystalline powders of Bi$_2$Se$_3$ and Bi$_2$Te$_3$, respectively. The spin-lattice ($T_1$) relaxation is …

2015-06-21cond-mat.mtrl-sci

Thermoelectric and galvanomagnetic properties of bismuth chalcogenide nanostructured hetero-epitaxial films

Hot wall technique was used to grow block single crystal films of Bi_2Te_3 and solid solutions of Bi_(0.5)Sb_(1.5)Te_3 on mica (muscovite) substrates. X-ray diffraction studies demonstrated that the crystalline c-axis in the films was normal to the substrate plane. Seebeck coefficient, electrical conductivity and magnetoresistivity tensor components were measured at various orientations of magnetic and electric fields in the temperature interval 77-300 K and magnetic field up to 14 T. Scattering mechanism of charge carriers in the films were studied using temperature dependences of the degener…

2014-07-12cond-mat.mtrl-sci

Non-magnetic ground state of Ni adatoms on Te-terminated bismuth chalcogenide topological insulators

We report on the quenching of single Ni adatom moments on Te-terminated Bi2Te2Se and Bi2Te3 topological insulator surfaces. The effect becomes manifested as a missing X-ray magnetic circular dichroism for resonant L3,2 transitions into partially filled Ni 3d states of occupancy n_d = 9.2. On the basis of a comparative study of Ni and Fe using scanning tunneling microscopy and ab initio calculations we are able to relate the element specific moment formation to a local Stoner criterion. While Fe adatoms form large spin moments of m_s = 2.54 mu_B with out-of-plane anisotropy due to a sufficientl…

2016-03-31cond-mat.mtrl-sci

更多相关论文收起更多论文

拓扑绝缘体Bi2Te3薄膜中的单域成像

Single-domain imaging in topological insulator Bi2Te3 thin films

本研究通过原子力显微镜对比Bi2Se3和Bi2Te3在Al2O3上的形貌，发现Bi2Te3实现单域，提出孪晶界形成与范德华间隙层间相互作用相关，而非应变或缺陷。

2024-11-06cond-mat.mes-hallcond-mat.mtrl-sci

Electrical properties of Bi-implanted amorphous chalcogenide films

The impact of Bi implantation on the conductivity and the thermopower of amorphous chalcogenide films is investigated. Incorporation of Bi in Ge-Sb-Te and GeTe results in enhanced conductivity. The negative Seebeck coefficient confirms onset of the electron conductivity in GeTe implanted with Bi at a dose of 2x1016 cm-2. The enhanced conductivity is accompanied by defect accumulation in the films upon implantation as is inferred by using analysis of the space-charge limited current. The results indicate that native coordination defects in lone-pair semiconductors can be deactivated by means of…

2014-12-09cond-mat.mtrl-sci

不同厚度外延In₂Te₃薄膜的稳健材料特性

Robust Material Properties in Epitaxial In$_2$Te$_3$ Thin Films Across Varying Thicknesses

本研究探究了不同厚度外延In₂Te₃薄膜的材料特性，发现其特性对厚度依赖性极小（与其他硫属化物形成对比），并通过多种表征技术揭示了这一现象源于其共价键结构。

2025-10-21cond-mat.mtrl-sci

Synthesis, Crystal Structure, and Thermoelectric Properties of Layered Antimony Selenides REOSbSe2 (RE = La, Ce)

Inspired by the recent first-principles calculations showing the high thermoelectric performance of layered pnictogen chalcogenides, we experimentally characterise the crystal structure and high-temperature transport properties of the layered antimony selenides REOSbSe2 (RE = La, Ce). The crystal structure of REOSbSe2 was the tetragonal P4/nmm space group, consisting of alternate stacks of SbSe2 and REO layers. These two compounds were n-type semiconductors. The optical band gaps of LaOSbSe2 and CeOSbSe2 were evaluated to be 1.0 and 0.6 eV, respectively. The room-temperature thermal conductivi…

2018-05-21cond-mat.mtrl-sci

Multigap superconductivity in the new BiCh$_{2}$-based layered superconductor La$_\mathrm{0.7}$Ce$_\mathrm{0.3}$OBiSSe

The layered bismuth oxy-sulfide materials, which are structurally related to the Fe-pnictides/chalcogenides and cuprates superconductors, have brought substantial attention for understanding the physics of reduced dimensional superconductors. We have examined the pairing symmetry of recently discovered BiCh$_2$-based superconductor, La$_\mathrm{1-x}$Ce$_\mathrm{x}$OBiSSe with $x$ = 0.3, through transverse field (TF) muon spin rotation measurement, in addition we present the results of magnetization, resistivity and zero field (ZF) muon spin relaxation measurements. Bulk superconductivity has b…

2020-07-07cond-mat.mtrl-scicond-mat.str-elcond-mat.supr-con

Nanoscale Determination of the Mass Enhancement Factor in the Lightly-Doped Bulk Insulator Lead Selenide

Bismuth chalcogenides and lead telluride/selenide alloys exhibit exceptional thermoelectric properties which could be harnessed for power generation and device applications. Since phonons play a significant role in achieving these desired properties, quantifying the interaction between phonons and electrons, which is encoded in the Eliashberg function of a material, is of immense importance. However, its precise extraction has in part been limited due to the lack of local experimental probes. Here we construct a method to directly extract the Eliashberg function using Landau level spectroscopy…

2015-02-16cond-mat.mes-hallcond-mat.mtrl-sci

Thermoelectric properties of topological insulator $\mathrm{BaSn_2}$

Recently, $\mathrm{BaSn_2}$ is predicted to be a strong topological insulator by the first-principle calculations. It is well known that topological insulator has a close connection to thermoelectric material, such as $\mathrm{Bi_2Te_3}$ family. In this work, we investigate thermoelectric properties of $\mathrm{BaSn_2}$ by the first-principles combined with Boltzmann transport theory. The electronic part is carried out by a modified Becke and Johnson (mBJ) exchange potential, including spin-orbit coupling (SOC), while the phonon part is performed using generalized gradient approximation (GGA).…

2016-08-20cond-mat.mtrl-sci