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Li R, Song W, Miao W, Yu Z, Wang Z, Yang S, Gao Y, Wang Y, Chen F, Geng Z, Yang L, Xu J, Feng X, Wang T, Zang Y, Li L, Shang R, Xue Q, He K, Zhang H. Selective-Area-Grown PbTe-Pb Planar Josephson Junctions for Quantum Devices. Nano Lett 2024; 24:4658-4664. [PMID: 38563608 DOI: 10.1021/acs.nanolett.4c00900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Planar Josephson junctions are predicted to host Majorana zero modes. The material platforms in previous studies are two-dimensional electron gases (InAs, InSb, InAsSb, and HgTe) coupled to a superconductor such as Al or Nb. Here, we introduce a new material platform for planar JJs, the PbTe-Pb hybrid. The semiconductor, PbTe, was grown as a thin film via selective area epitaxy. The Josephson junction was defined by a shadow wall during the deposition of superconductor Pb. Scanning transmission electron microscopy reveals a sharp semiconductor-superconductor interface. Gate-tunable supercurrents and multiple Andreev reflections are observed. A perpendicular magnetic field causes interference patterns of the switching current, exhibiting Fraunhofer-like and SQUID-like behaviors. We further demonstrate a prototype device for Majorana detection wherein phase bias and tunneling spectroscopy are applicable.
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Affiliation(s)
- Ruidong Li
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Wenyu Song
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Wentao Miao
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Zehao Yu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Zhaoyu Wang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Shuai Yang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Yichun Gao
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Yuhao Wang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Fangting Chen
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Zuhan Geng
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Lining Yang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Jiaye Xu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Xiao Feng
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
- Hefei National Laboratory, Hefei 230088, China
| | - Tiantian Wang
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Hefei National Laboratory, Hefei 230088, China
| | - Yunyi Zang
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Hefei National Laboratory, Hefei 230088, China
| | - Lin Li
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - Runan Shang
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Hefei National Laboratory, Hefei 230088, China
| | - Qikun Xue
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
- Hefei National Laboratory, Hefei 230088, China
- Southern University of Science and Technology, Shenzhen 518055, China
| | - Ke He
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
- Hefei National Laboratory, Hefei 230088, China
| | - Hao Zhang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
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Jiang Z, Li E, Shi R, Feng B, Chen JL, Peng Y, Liu C, Miao L. Effective Nonstoichiometric Strategy Combined Post-annealing Process for Boosting Thermoelectric Properties in n-Type PbTe. ACS Appl Mater Interfaces 2024; 16:19048-19056. [PMID: 38578807 DOI: 10.1021/acsami.4c03051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/07/2024]
Abstract
The intrinsic low electrical properties have hindered the enhancement of thermoelectric performance for n-type PbTe over a long period of time, primarily due to the generation of intrinsic Pb vacancies and other defects. In this work, PbTe samples with nonstoichiometric excess Pb atoms were successfully prepared by a melting reaction followed by spark plasma sintering. First, the introduction of precisely controlled excess Pb atoms has effectively eliminated the typical p-n transition phenomenon in PbTe systems by suppressing the generation of Pb vacancies. Further, the vacuum annealing process employed in nonstoichiometric samples increases the carrier mobility significantly because of the improved crystallinity and the lowered holes. Thus, the Hall mobility was optimized from 754.3 to 1215.9 cm2 V-1 s-1, while the power factor was ultimately elevated from 3087.8 to 4565.7 μW m-1 K-2 for the Pb1.03Te sample at 323 K. Benefited from the enhanced electrical transport properties near room temperature, an average zT ∼ 1.03 ranging from 323 to 723 K was achieved, demonstrating an outstanding performance in n-type nondoped PbTe. This work provides guidance for optimizing the thermoelectric performance of n-type PbTe and relevant telluride by reducing vacancies and other defects.
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Affiliation(s)
- Zexin Jiang
- Guangxi Key Laboratory of Information Materials, Engineering Research Center of Electronic Information Materials and Devices, Ministry of Education, School of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China
| | - Enliang Li
- China Electronic Product Reliability and Environmental Testing Research Institute, Guangzhou 510610, China
| | - Runze Shi
- Guangxi Key Laboratory of Information Materials, Engineering Research Center of Electronic Information Materials and Devices, Ministry of Education, School of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China
| | - Baoquan Feng
- Guangxi Key Laboratory of Information Materials, Engineering Research Center of Electronic Information Materials and Devices, Ministry of Education, School of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China
| | - Jun-Liang Chen
- Guangxi Key Laboratory of Information Materials, Engineering Research Center of Electronic Information Materials and Devices, Ministry of Education, School of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China
| | - Ying Peng
- Guangxi Key Laboratory of Precision Navigation Technology and Application, School of Information and Communication, Guilin University of Electronic Technology, Guilin 541004, China
| | - Chengyan Liu
- Guangxi Key Laboratory of Information Materials, Engineering Research Center of Electronic Information Materials and Devices, Ministry of Education, School of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China
| | - Lei Miao
- Guangxi Key Laboratory for Relativity Astrophysics, State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures, School of Physical Science and Technology, Guangxi University, Nanning 530004, China
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3
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Wang Y, Chen F, Song W, Geng Z, Yu Z, Yang L, Gao Y, Li R, Yang S, Miao W, Xu W, Wang Z, Xia Z, Song HD, Feng X, Wang T, Zang Y, Li L, Shang R, Xue Q, He K, Zhang H. Ballistic PbTe Nanowire Devices. Nano Lett 2023. [PMID: 37948302 DOI: 10.1021/acs.nanolett.3c03604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
Disorder is the primary obstacle in the current Majorana nanowire experiments. Reducing disorder or achieving ballistic transport is thus of paramount importance. In clean and ballistic nanowire devices, quantized conductance is expected, with plateau quality serving as a benchmark for disorder assessment. Here, we introduce ballistic PbTe nanowire devices grown by using the selective-area-growth (SAG) technique. Quantized conductance plateaus in units of 2e2/h are observed at zero magnetic field. This observation represents an advancement in diminishing disorder within SAG nanowires as most of the previously studied SAG nanowires (InSb or InAs) have not exhibited zero-field ballistic transport. Notably, the plateau values indicate that the ubiquitous valley degeneracy in PbTe is lifted in nanowire devices. This degeneracy lifting addresses an additional concern in the pursuit of Majorana realization. Moreover, these ballistic PbTe nanowires may enable the search for clean signatures of the spin-orbit helical gap in future devices.
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Affiliation(s)
- Yuhao Wang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Fangting Chen
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Wenyu Song
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Zuhan Geng
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Zehao Yu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Lining Yang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Yichun Gao
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Ruidong Li
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Shuai Yang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Wentao Miao
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Wei Xu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Zhaoyu Wang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Zezhou Xia
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Hua-Ding Song
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - Xiao Feng
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
- Hefei National Laboratory, Hefei 230088, China
| | - Tiantian Wang
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Hefei National Laboratory, Hefei 230088, China
| | - Yunyi Zang
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Hefei National Laboratory, Hefei 230088, China
| | - Lin Li
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - Runan Shang
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Hefei National Laboratory, Hefei 230088, China
| | - Qikun Xue
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
- Hefei National Laboratory, Hefei 230088, China
- Southern University of Science and Technology, Shenzhen 518055, China
| | - Ke He
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
- Hefei National Laboratory, Hefei 230088, China
| | - Hao Zhang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
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4
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Jayachandran B, Dasgupta T, Sivaprahasam D. Highly Stable Metal─Na 0.02Pb 0.98Te Contacts for Medium Temperature Thermoelectric Devices. ACS Appl Mater Interfaces 2023; 15:22231-22240. [PMID: 37114800 DOI: 10.1021/acsami.3c01623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
In the medium temperature (600-850 K) range, Na0.02Pb0.98Te is a highly efficient p-type thermoelectric compound. Device fabrication utilizing this compound for power generation demands highly stable low-contact resistance contacts with metal electrodes. This work investigates the microstructural, electrical, mechanical, and thermochemical stability of Na0.02Pb0.98Te-metal (Ni, Fe, and Co) contacts made by a one-step vacuum hot pressing process. Direct contact mostly resulted in either an interface with poor mechanical integrity, as in Co and Fe, or poisoning of the TE compound, as in the case of Ni, which results in high specific contact resistance (rc). In Ni and Co, adding a SnTe interlayer lowers the rc and strengthens the contact. It does not, however, effectively stop Ni from diffusing into Na0.02Pb0.98Te. The bonding is poor in the Fe/SnTe/Na0.02Pb0.98Te contacts due to the absence of any reaction at the Fe/SnTe interface. A composite buffer layer Co + 75 vol % SnTe with SnTe improves the mechanical stability of the Co contact with moderately lesser rc than pure SnTe alone. However, a similar approach with Fe does not yield stable contact. The Co/Co + 75 vol % SnTe/SnTe/Na0.02Pb0.98Te contact exhibits rc less than 50 μΩ cm2 and has good microstructural and mechanical stability after annealing at 723 K for 170 h.
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Affiliation(s)
- Babu Jayachandran
- Centre for Automotive Energy Materials, International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), IITM Research Park, Chennai, Tamilnadu 600 113, India
- Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai, Maharashtra 400 076, India
| | - Titas Dasgupta
- Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai, Maharashtra 400 076, India
| | - Duraisamy Sivaprahasam
- Centre for Automotive Energy Materials, International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), IITM Research Park, Chennai, Tamilnadu 600 113, India
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5
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Kawamura S, Fuseya Y. Orbital magnetization of three-dimensional Dirac electrons in the quantum limit. J Phys Condens Matter 2023; 35:225801. [PMID: 36921346 DOI: 10.1088/1361-648x/acc4a2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Accepted: 03/15/2023] [Indexed: 06/18/2023]
Abstract
In this study, we evaluated the dependence of magnetization of three-dimensional Dirac electrons in the quantum limit on the magnetic field and temperature. The magnetization was calculated by differentiating the free energy with respect to the magnetic field. The field and temperature dependence of the chemical potential were entirely considered under the canonical ensemble condition. The total magnetizationMconsisted of two contributions from the conductionMcand valenceMvbands.Mvwas insensitive to temperature and exhibited sub-linear field dependence, which is consistent with the previous research on Dirac electrons. By contrast,Mcwas sensitive to both temperature and magnetic field, yielding a non-trivial contribution to the totalM. As a result, the properties of totalMchanged at approximatelykBT≃EF, whereEFis the Fermi energy measured from the band bottom andkBis the Boltzmann constant. At low temperatureskBT≲EF,Mexhibited sub-linear field dependence, whereasMexhibited super-linear field dependence at high temperatureskBT≳EF. This qualitative change in the field dependence ofMwill play a significant role in the magnetization of Dirac electrons with smallEF.
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Affiliation(s)
- Shogo Kawamura
- Department of Engineering Science, University of Electro-Communications, Chofu, Tokyo 182-8585, Japan
| | - Yuki Fuseya
- Department of Engineering Science, University of Electro-Communications, Chofu, Tokyo 182-8585, Japan
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6
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Liu M, Zhang X, Wu Y, Bu Z, Chen Z, Li W, Pei Y. Screening Metal Electrodes for Thermoelectric PbTe. ACS Appl Mater Interfaces 2023; 15:6169-6176. [PMID: 36656557 DOI: 10.1021/acsami.2c19820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Historically, both p- and n-type PbTe show extraordinary thermoelectric figures of merit within 300-600 °C for power generation applications. A full realization of the potential of these high-performance thermoelectric materials on a device level largely depends on the electrical and thermal contacts with the metal electrodes. Chemical inertness with a slow diffusion could be an important criterion for the selection of metal electrodes. In this work, the diffusion of the total 12 potential metal electrodes in PbTe diffusion couples are focused on and sorted, suggesting the superiority of Co as an electrode for its low diffusion coefficient and interfacial contact resistivity, inertial to PbTe and compatibility in temperature for sintering. The strategy used in this work is believed to be applicable to the selection of electrodes for other thermoelectric materials.
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Affiliation(s)
- Min Liu
- Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji Univ., 4800 Caoan Road, Shanghai201804, China
| | - Xinyue Zhang
- Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji Univ., 4800 Caoan Road, Shanghai201804, China
| | - Yixuan Wu
- Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji Univ., 4800 Caoan Road, Shanghai201804, China
| | - Zhonglin Bu
- Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji Univ., 4800 Caoan Road, Shanghai201804, China
| | - Zhiwei Chen
- Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji Univ., 4800 Caoan Road, Shanghai201804, China
| | - Wen Li
- Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji Univ., 4800 Caoan Road, Shanghai201804, China
| | - Yanzhong Pei
- Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji Univ., 4800 Caoan Road, Shanghai201804, China
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7
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ten Kate S, Ritter MF, Fuhrer A, Jung J, Schellingerhout SG, Bakkers EPAM, Riel H, Nichele F. Small Charging Energies and g-Factor Anisotropy in PbTe Quantum Dots. Nano Lett 2022; 22:7049-7056. [PMID: 35998346 PMCID: PMC9479220 DOI: 10.1021/acs.nanolett.2c01943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 08/15/2022] [Indexed: 06/15/2023]
Abstract
PbTe is a semiconductor with promising properties for topological quantum computing applications. Here, we characterize electron quantum dots in PbTe nanowires selectively grown on InP. Charge stability diagrams at zero magnetic field reveal large even-odd spacing between Coulomb blockade peaks, charging energies below 140 μeV and Kondo peaks in odd Coulomb diamonds. We attribute the large even-odd spacing to the large dielectric constant and small effective electron mass of PbTe. By studying the Zeeman-induced level and Kondo splitting in finite magnetic fields, we extract the electron g-factor as a function of magnetic field direction. We find the g-factor tensor to be highly anisotropic with principal g-factors ranging from 0.9 to 22.4 and to depend on the electronic configuration of the devices. These results indicate strong Rashba spin-orbit interaction in our PbTe quantum dots.
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Affiliation(s)
- Sofieke
C. ten Kate
- IBM
Research Europe, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
- University
of Twente, Drienerlolaan
5, 7522 NB Enschede, Netherlands
| | - Markus F. Ritter
- IBM
Research Europe, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
| | - Andreas Fuhrer
- IBM
Research Europe, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
| | - Jason Jung
- Eindhoven
University of Technology, 5600 MB Eindhoven, The Netherlands
| | | | | | - Heike Riel
- IBM
Research Europe, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
| | - Fabrizio Nichele
- IBM
Research Europe, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
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Lu X, Lu W, Gao J, Liu Y, Huang J, Yan P, Fan Y, Jiang W. Processing High-Performance Thermoelectric Materials in a Green Way: A Proof of Concept in Cold Sintered PbTe0.94Se 0.06. ACS Appl Mater Interfaces 2022; 14:37937-37946. [PMID: 35960808 DOI: 10.1021/acsami.2c09065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
For years, most of the advanced polycrystalline thermoelectric (TE) materials are fabricated by spark plasma sintering (SPS) in the research field, mainly because of its high processing efficiency. However, issues like high energy consumption and an expensive apparatus have prevented the application of this strategy in industry. Herein, taking PbTe0.94Se0.06 (PTS) as a typical n-type mid-temperature material, we demonstrate that the cold sintering process (CSP) can serve as a green and cost-effective technology for preparing advanced TE materials. By selecting the solvothermal precursors as liquid sintering aids, the CSP-densified PTS shows a maximum figure of merit of 0.96 at 700 K, which is on par with, if not better than, the reported similar materials prepared by SPS. This remarkable performance is ascribed to the distinct densification procedure in the CSP: (1) the ultralow temperature alleviates the precipitation of Pb, which preserves the high carrier concentration of PTS; (2) the transient liquid phase forms intimate grain boundaries comparable to the high-temperature sintered one, leading to a high carrier mobility; (3) the dissolution-precipitation process greatly restrains the coarsening of precipitates, which effectively suppresses the bipolar effect and lattice thermal conductivity due to enhanced scattering. We believe that these results can greatly encourage the application of CSP in the future development of TE materials.
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Affiliation(s)
- Xueping Lu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Institute of Functional Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
| | - Wenbin Lu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Institute of Functional Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
| | - Jie Gao
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Institute of Functional Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
| | - Yongping Liu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Institute of Functional Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
| | - Jilong Huang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Institute of Functional Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
| | - Peng Yan
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Institute of Functional Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
| | - Yuchi Fan
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Institute of Functional Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
| | - Wan Jiang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Institute of Functional Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
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Wędrychowicz A, Cieniek B, Stefaniuk I, Virt I, Śliwa R. Electron Paramagnetic Resonance Study of PbSe, PbTe, and PbTe:In Semiconductors Obtained by the Pulsed Laser Deposition Method. Molecules 2022; 27:4381. [PMID: 35889254 DOI: 10.3390/molecules27144381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/29/2022] [Accepted: 07/04/2022] [Indexed: 11/21/2022]
Abstract
The magnetic properties of lead selenide (PbSe) and indium-doped lead telluride (PbTe:In) composites have been studied by using the electron paramagnetic resonance (EPR) technique. The samples were obtained by using the pulsed laser deposition method (PLD). Temperature dependences of the EPR spectra were obtained. The analysis of the temperature dependencies of the integral intensity of the EPR spectra was performed using the Curie–Weiss law. In these materials, the paramagnetic centers of Pb1+ and Pb3+ ions were identified. The results are discussed.
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10
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Park S, Ryu B, Park S. Off-Centered Pb Interstitials in PbTe. Materials (Basel) 2022; 15:ma15041272. [PMID: 35207814 PMCID: PMC8879023 DOI: 10.3390/ma15041272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/18/2022] [Accepted: 01/30/2022] [Indexed: 11/16/2022]
Abstract
Previous calculations have demonstrated that Te vacancies are energetically the major defects in PbTe. However, the Pb interstitials are also important because experiments have shown that the volume of Pb-rich PbTe increases at a higher Pb content. In this study, density functional theory calculations were used to investigate the defect properties of low-symmetry Pb interstitials in PbTe. By breaking the higher symmetry imposed on the on-centered interstitial defects, the lowest ground state of Pb interstitial defects is off-centered along the [1¯1¯1¯] direction. Because of the four multi-stable structures with low defect-formation energies, the defect density of Pb interstitials is expected to be approximately six times higher than previous predictions for PbTe synthesized at 900 K. In contrast to the on-centered Pb interstitials, the off-centered Pb interstitials in PbTe can exhibit long-range lattice relaxation in the [111] direction beyond a distance of 1 nm, indicating the potential formation of weak local dipoles. This result provides an alternative explanation for the emphanitic anharmonicity of PbTe in the high-temperature regime.
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11
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Cao Y, Bai H, Li Z, Zhang Z, Tang Y, Su X, Wu J, Tang X. Zn-Induced Defect Complexity for the High Thermoelectric Performance of n-Type PbTe Compounds. ACS Appl Mater Interfaces 2021; 13:43134-43143. [PMID: 34479449 DOI: 10.1021/acsami.1c14518] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Although defect engineering is the core strategy to improve thermoelectric properties, there are limited methods to effectively modulate the designed defects. Herein, we demonstrate that a high ZT value of 1.36 at 775 K and a high average ZT value of 0.99 in the temperature range from 300 to 825 K are realized in Zn-containing PbTe by designing complex defects. By combining first-principles calculations and experiments, we show that Zn atoms occupy both Pb sites and interstitial sites in PbTe and couple with each other. The contraction stress induced via substitutional Zn on Pb sites alleviates the swelling stress by Zn atoms occupying the interstitial sites and promotes the solubility of interstitial Zn atoms in the structure of PbTe. The stabilization of Zn impurity as a complex defect extends the region of PbTe phase stability toward Pb0.995Zn0.02Te, while the solid solution region in the other direction of the ternary phase diagram is much smaller. The evolution of defects in PbTe was further explicitly corroborated by aberration-corrected scanning transmission electron microscopy (Cs-corrected STEM) and positron annihilation measurement. The Zn atoms compensate the Pb vacancies (VPb) and Zn interstitials (Zni) significantly improve the electron concentration, producing a high carrier mobility of 1467.7 cm2 V-1 s-1 for the Pb0.995Zn0.02Te sample. A high power factor of 4.11 mW m-1 K-2 is achieved for the Pb0.995Zn0.02Te sample at 306 K. This work provides new insights into understanding the nature and evolution of the defects in n-type PbTe as well as improving the electronic and thermal transport properties toward higher thermoelectric performance.
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Affiliation(s)
- Yu Cao
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
| | - Hui Bai
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
- Nanostructure Research Center, Wuhan University of Technology, Wuhan 430070, China
| | - Zhi Li
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
- Department of Chemistry, Northwestern University, Evanston, Illinois 60201, United States
| | - Zhengkai Zhang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
| | - Yingfei Tang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
- International School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Xianli Su
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
| | - Jinsong Wu
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
- Nanostructure Research Center, Wuhan University of Technology, Wuhan 430070, China
| | - Xinfeng Tang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
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12
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Zelenina I, Veremchuk I, Grin Y, Simon P. In Situ Observation of Electron-Beam-Induced Formation of Nano-Structures in PbTe. Nanomaterials (Basel) 2021; 11:E163. [PMID: 33435228 DOI: 10.3390/nano11010163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 01/06/2021] [Accepted: 01/07/2021] [Indexed: 11/17/2022]
Abstract
Nano-scaled thermoelectric materials attract significant interest due to their improved physical properties as compared to bulk materials. Well-shaped nanoparticles such as nano-bars and nano-cubes were observed in the known thermoelectric material PbTe. Their extended two-dimensional nano-layer arrangements form directly in situ through electron-beam treatment in the transmission electron microscope. The experiments show the atomistic depletion mechanism of the initial crystal and the recrystallization of PbTe nanoparticles out of the microparticles due to the local atomic-scale transport via the gas phase beyond a threshold current density of the beam.
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13
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Gite AB, Palve BM, Gaikwad VB, Jain GH, Pathan HM, Haj Bloukh S, Edis Z. A Facile Chemical Synthesis of PbTe Nanostructures at Room Temperature. Nanomaterials (Basel) 2020; 10:E1915. [PMID: 32992952 DOI: 10.3390/nano10101915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/23/2020] [Accepted: 09/23/2020] [Indexed: 11/17/2022]
Abstract
Thermoelectric (TE) materials are possible solutions of the current problems in the energy sector to overcome environmental pollution, increasing energy demand and the decline of natural resources. Thermoelectric materials are a promising alternative for the conversion of waste heat to electricity. Nanocrystalline PbTe powder was synthesized by a simple chemical method at room temperature and systematically investigated at various durations as samples A1-A5. Fourier Transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), microstructural analysis by scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) confirmed the composition of the samples. TE parameters as thermo-emf of samples A1-A5 and electrical conductivity were measured. The cyclic voltammetry gives a band gap of 0.25 eV, which is in agreement with the optical band gap of the material. The A4 sample has an average crystal size of 36 nm with preferred orientation in (200) verifying the cubic morphology. The obtained TE parameters are beneficial for the non-uniform TE materials which might be due to strong current boundary scattering and extremely low thermal conductivity of the samples.
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14
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Wu Y, Nan P, Chen Z, Zeng Z, Liu R, Dong H, Xie L, Xiao Y, Chen Z, Gu H, Li W, Chen Y, Ge B, Pei Y. Thermoelectric Enhancements in PbTe Alloys Due to Dislocation-Induced Strains and Converged Bands. Adv Sci (Weinh) 2020; 7:1902628. [PMID: 32596105 PMCID: PMC7312309 DOI: 10.1002/advs.201902628] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 01/07/2020] [Indexed: 05/03/2023]
Abstract
In-grain dislocation-induced lattice strain fluctuations are recently revealed as an effective avenue for minimizing the lattice thermal conductivity. This effect could be integratable with electronic enhancements such as by band convergence, for a great advancement in thermoelectric performance. This motivates the current work to focus on the thermoelectric enhancements of p-type PbTe alloys, where monotelluride-alloying and Na-doping are used for a simultaneous manipulation on both dislocation and band structures. As confirmed by synchrotron X-ray diffractions and Raman measurements, the resultant dense in-grain dislocations induce lattice strain fluctuations for broadening the phonon dispersion, leading to an exceptionally low lattice thermal conductivity of ≈0. 4 W m-K-1. Band structure calculations reveal the convergence of valence bands due to monotelluride-alloying. Eventually, the integration of both electronic and thermal improvements lead to a realization of an extraordinary figure of merit zT of ≈2.5 in Na0.03Eu0.03Cd0.03Pb0.91Te alloy at 850 K.
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Affiliation(s)
- Yixuan Wu
- Interdisciplinary Materials Research CenterSchool of Materials Science and EngineeringTongji University4800 Caoan Rd.Shanghai201804China
| | - Pengfei Nan
- Institute of Physical Science and Information TechnologyAnhui UniversityHefei230601China
| | - Zhiwei Chen
- Interdisciplinary Materials Research CenterSchool of Materials Science and EngineeringTongji University4800 Caoan Rd.Shanghai201804China
| | - Zezhu Zeng
- Department of Mechanical EngineeringThe University of Hong KongPokfulam RoadHong Kong SARChina
| | - Ruiheng Liu
- State Key Laboratory of High Performance Ceramics and Superfine MicrostructureShanghai Institute of CeramicsCASShanghai200050China
| | - Hongliang Dong
- Center for High Pressure Science & Technology Advanced ResearchShanghai201203China
| | - Li Xie
- State Key Laboratory of High Performance Ceramics and Superfine MicrostructureShanghai Institute of CeramicsCASShanghai200050China
| | - Youwei Xiao
- Interdisciplinary Materials Research CenterSchool of Materials Science and EngineeringTongji University4800 Caoan Rd.Shanghai201804China
| | - Zhiqiang Chen
- Center for High Pressure Science & Technology Advanced ResearchShanghai201203China
| | - Hongkai Gu
- Center for High Pressure Science & Technology Advanced ResearchShanghai201203China
- State Key Laboratory of Superhard MaterialsJilin UniversityChangchun130012China
| | - Wen Li
- Interdisciplinary Materials Research CenterSchool of Materials Science and EngineeringTongji University4800 Caoan Rd.Shanghai201804China
| | - Yue Chen
- Department of Mechanical EngineeringThe University of Hong KongPokfulam RoadHong Kong SARChina
| | - Binghui Ge
- Institute of Physical Science and Information TechnologyAnhui UniversityHefei230601China
| | - Yanzhong Pei
- Interdisciplinary Materials Research CenterSchool of Materials Science and EngineeringTongji University4800 Caoan Rd.Shanghai201804China
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15
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Mitani Y, Fuseya Y. Large longitudinal magnetoresistance of multivalley systems. J Phys Condens Matter 2020; 32:345802. [PMID: 32315988 DOI: 10.1088/1361-648x/ab8b9a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 04/21/2020] [Indexed: 06/11/2023]
Abstract
The longitudinal magnetoresistance (MR) is assumed to be hardly realized as the Lorentz force does not work on electrons when the magnetic field is parallel to the current. However, in some cases, longitudinal MR becomes large, which exceeds the transverse MR. To solve this problem, we have investigated the longitudinal MR considering multivalley contributions based on the classical MR theory. We have showed that the large longitudinal MR is caused by off-diagonal components of a mobility tensor. Our theoretical results agree with the experiments of large longitudinal MR in IV-VI semiconductors, especially in PbTe, for a wide range of temperatures, except for linear MR at low temperatures.
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Affiliation(s)
- Yuki Mitani
- Department of Engineering Science, University of Electro-Communications, Chofu, Tokyo 182-8585, Japan
| | - Yuki Fuseya
- Department of Engineering Science, University of Electro-Communications, Chofu, Tokyo 182-8585, Japan
- Institute for Advanced Science, University of Electro-Communications, Chofu, Tokyo 182-8585, Japan
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16
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Chen X, Baumgart H. Advances in Atomic Layer Deposition (ALD) Nanolaminate Synthesis of Thermoelectric Films in Porous Templates for Improved Seebeck Coefficient. Materials (Basel) 2020; 13:ma13061283. [PMID: 32178403 PMCID: PMC7143041 DOI: 10.3390/ma13061283] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 03/03/2020] [Accepted: 03/09/2020] [Indexed: 11/16/2022]
Abstract
Thermoelectrics is a green renewable energy technology which can significantly contribute to power generation due to its potential in generating electricity out of waste heat. The main challenge for the development of thermoelectrics is its low conversion efficiency. One key strategy to improve conversion efficiency is reducing the thermal conductivity of thermoelectric materials. In this paper, the state-of-the-art progresses made in improving thermoelectric materials are reviewed and discussed, focusing on phononic engineering via applying porous templates and ALD deposited nanolaminates structure. The effect of nanolaminates structure and porous templates on Seebeck coefficient, electrical conductivity and thermal conductivity, and hence in figure of merit zT of different types of materials system, including PnCs, lead chalcogenide-based nanostructured films on planar and porous templates, ZnO-based superlattice, and hybrid organic-inorganic superlattices, will be reviewed and discussed.
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Affiliation(s)
- Xin Chen
- Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, VA 23529, USA;
- Applied Research Center at Thomas Jefferson National Accelerator Laboratories, 12050 Jefferson Avenue, Suite 721, Newport News, VA 23606, USA
| | - Helmut Baumgart
- Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, VA 23529, USA;
- Applied Research Center at Thomas Jefferson National Accelerator Laboratories, 12050 Jefferson Avenue, Suite 721, Newport News, VA 23606, USA
- Correspondence:
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17
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Zhu T, Xie H, Zhang C, Cheng X, Zhang J, Poudeu PFP, Tan G, Yan Y, Liu W, Su X, Tang X. Enhanced Mechanical Properties of Na 0.02Pb 0.98Te/MoTe 2 Thermoelectric Composites Through in-Situ-Formed MoTe 2. ACS Appl Mater Interfaces 2019; 11:41472-41481. [PMID: 31610127 DOI: 10.1021/acsami.9b10019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Lead telluride (PbTe) is one of the best thermoelectric materials in the intermediate temperature range, which shows great potential for waste heat recycling. However, its low strength and high brittleness limit its large-scale application because the thermoelectric device usually undergoes mechanical vibration, mechanical and/or thermal cycling, and thermal shock in service. In this study, the enhanced mechanical properties and thermoelectric properties of PbTe are realized simultaneously through introducing dispersive transition-metal dichalcogenide MoTe2 (molybdenum telluride). The in-situ-formed MoTe2 precipitations with a size in the range from 2 to 5 μm and the tight and smooth interface between the PbTe matrix and precipitates contribute to the obvious crack deflection, crack bridging, and pull-out of long grains, dissipating more energy during crack propagation and resulting in a tortuous propagation path. Because of the toughening and the dispersion strengthening effect, the compressive strength, bending strength, and fracture toughness of the sample with a composite amount of 1% are 109 MPa and 50 MPa and 0.65 MPa·m1/2, respectively, which are increased by about 37, 117, and 67% compared to the Na0.02Pb0.98Te matrix. Additionally, the in situ MoTe2 precipitates intensify the interface phonon scattering and thus decrease the lattice thermal conductivity. As a result, the Na0.02Pb0.98Te-1%MoTe2 sample achieves a maximum ZT value of 1.46 at 700 K, which is 11% higher than that of Na0.02Pb0.98Te without any MoTe2 nanoprecipitation.
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Affiliation(s)
- Ting Zhu
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing , Wuhan University of Technology , Wuhan 430070 , China
| | - Hongyao Xie
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing , Wuhan University of Technology , Wuhan 430070 , China
| | - Cheng Zhang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing , Wuhan University of Technology , Wuhan 430070 , China
| | - Xin Cheng
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing , Wuhan University of Technology , Wuhan 430070 , China
| | - Jian Zhang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing , Wuhan University of Technology , Wuhan 430070 , China
| | - Pierre Ferdinand Poudeu Poudeu
- Laboratory for Emerging Energy and Electronic Materials (LE3M), Department of Materials Science and Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Gangjian Tan
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing , Wuhan University of Technology , Wuhan 430070 , China
| | - Yonggao Yan
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing , Wuhan University of Technology , Wuhan 430070 , China
| | - Wei Liu
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing , Wuhan University of Technology , Wuhan 430070 , China
| | - Xianli Su
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing , Wuhan University of Technology , Wuhan 430070 , China
| | - Xinfeng Tang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing , Wuhan University of Technology , Wuhan 430070 , China
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18
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Ondry JC, Hauwiller MR, Alivisatos AP. Dynamics and Removal Pathway of Edge Dislocations in Imperfectly Attached PbTe Nanocrystal Pairs: Toward Design Rules for Oriented Attachment. ACS Nano 2018; 12:3178-3189. [PMID: 29470056 DOI: 10.1021/acsnano.8b00638] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Using in situ high-resolution TEM, we study the structure and dynamics of well-defined edge dislocations in imperfectly attached PbTe nanocrystals. We identify that attachment of PbTe nanocrystals on both {100} and {110} facets gives rise to b = a/2⟨110⟩ edge dislocations. Based on the Burgers vector of individual dislocations, we can identify the glide plane of the dislocations. We observe that defects in particles attached on {100} facets have glide planes that quickly intersect the surface, and HRTEM movies show that the defects follow the glide plane to the surface. For {110} attached particles, the glide plane is collinear with the attachment direction, which does not provide an easy path for the dislocation to reach the surface. Indeed, HRTEM movies of dislocations for {110} attached particles show that defect removal is much slower. Further, we observe conversion from pure edge dislocations in imperfectly attached particles to dislocations with mixed edge and screw character, which has important implications for crystal growth. Finally, we observe that dislocations initially closer to the surface have a higher speed of removal, consistent with the strong dislocation free surface attractive force. Our results provide important design rules for defect-free attachment of preformed nanocrystals into epitaxial assemblies.
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Affiliation(s)
- Justin C Ondry
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
- Materials Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Matthew R Hauwiller
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
- Materials Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - A Paul Alivisatos
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
- Materials Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
- Department of Materials Science and Engineering , University of California , Berkeley , California 94720 , United States
- Kavli Energy NanoScience Institute , Berkeley , California 94720 , United States
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19
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Ben-Ayoun D, Sadia Y, Gelbstein Y. Compatibility between Co-Metallized PbTe Thermoelectric Legs and an Ag-Cu-In Brazing Alloy. Materials (Basel) 2018; 11:ma11010099. [PMID: 29320430 PMCID: PMC5793597 DOI: 10.3390/ma11010099] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 01/05/2018] [Accepted: 01/08/2018] [Indexed: 11/28/2022]
Abstract
In thermoelectric (TE) generators, maximizing the efficiency of conversion of direct heat to electricity requires the reduction of any thermal and electrical contact resistances between the TE legs and the metallic contacts. This requirement is especially challenging in the development of intermediate to high-temperature TE generators. PbTe-based TE materials are known to be highly efficient up to temperatures of around 500 °C; however, only a few practical TE generators based on these materials are currently commercially available. One reason for that is the insufficient bonding techniques between the TE legs and the hot-side metallic contacts. The current research is focused on the interaction between cobalt-metallized n-type 9.104 × 10−3 mol % PbI2-doped PbTe TE legs and the Ag0.32Cu0.43In0.25 brazing alloy, which is free of volatile species. Clear and fine interfaces without any noticeable formation of adverse brittle intermetallic compounds were observed following prolonged thermal treatment testing. Moreover, a reasonable electrical contact resistance of ~2.25 mΩmm2 was observed upon brazing at 600 °C, highlighting the potential of such contacts while developing practical PbTe-based TE generators.
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Affiliation(s)
- Dana Ben-Ayoun
- Unit of Energy Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
| | - Yatir Sadia
- Department of Materials Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
| | - Yaniv Gelbstein
- Unit of Energy Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
- Department of Materials Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
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20
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Kumar A, Kundu S, Samantaray D, Kundu P, Zanaga D, Bals S, Ravishankar N. Designing Diameter-Modulated Heterostructure Nanowires of PbTe/Te by Controlled Dewetting. Nano Lett 2017; 17:7226-7233. [PMID: 29185765 DOI: 10.1021/acs.nanolett.7b02442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Heterostructures consisting of semiconductors with controlled morphology and interfaces find applications in many fields. A range of axial, radial, and diameter-modulated nanostructures have been synthesized primarily using vapor phase methods. Here, we present a simple wet chemical routine to synthesize heterostructures of PbTe/Te using Te nanowires as templates. A morphology evolution study for the formation of these heterostructures has been performed. On the basis of these control experiments, a pathway for the formation of these nanostructures is proposed. Reduction of a Pb precursor to Pb on Te nanowire templates followed by interdiffusion of Pb/Te leads to the formation of a thin shell of PbTe on the Te wires. Controlled dewetting of the thin shell leads to the formation of cube-shaped PbTe that is periodically arranged on the Te wires. Using control experiments, we show that different reactions parameters like rate of addition of the reducing agent, concentration of Pb precursor and thickness of initial Te nanowire play a critical role in controlling the spacing between the PbTe cubes on the Te wires. Using simple surface energy arguments, we propose a mechanism for the formation of the hybrid. The principles presented are general and can be exploited for the synthesis of other nanoscale heterostructures.
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Affiliation(s)
- Abinash Kumar
- Materials Research Centre, Indian Institute of Science , Bangalore 560012, India
| | - Subhajit Kundu
- Materials Research Centre, Indian Institute of Science , Bangalore 560012, India
| | | | - Paromita Kundu
- Electron Microscopy for Materials Science (EMAT), University of Antwerp , Groenenborgerlaan 171, B-2020 Antwerp, Belgium
| | - Daniele Zanaga
- Electron Microscopy for Materials Science (EMAT), University of Antwerp , Groenenborgerlaan 171, B-2020 Antwerp, Belgium
| | - Sara Bals
- Electron Microscopy for Materials Science (EMAT), University of Antwerp , Groenenborgerlaan 171, B-2020 Antwerp, Belgium
| | - N Ravishankar
- Materials Research Centre, Indian Institute of Science , Bangalore 560012, India
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21
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Ginting D, Lin CC, Rathnam L, Hwang J, Kim W, Al Orabi RAR, Rhyee JS. Dataset on the electronic and thermal transport properties of quaternary compounds of ( PbTe) 0.95-x(PbSe) x(PbS) 0.05. Data Brief 2017; 13:233-41. [PMID: 28626789 DOI: 10.1016/j.dib.2017.05.041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The data presented in this article are related to the research article entitled "High thermoelectric performance in pseudo quaternary compounds of (PbTe)0.95-x (PbSe)x(PbS)0.05 by simultaneous band convergence and nano precipitation" (Ginting et al., 2017) [1]. We measured electrical and thermal transport properties such as temperature-dependent Hall carrier density nH , Hall mobility μH , thermal diffusivity D, heat capacity Cp , and power factor S2σ in (PbTe)0.95-x (PbSe)x(PbS)0.05 (x=0.0, 0.05, 0.10, 0.15, 0.20, 0.35, and 0.95) compounds with other related compounds from references. From the theoretical fitting of thermal conductivity κ, we found that the temperature-dependent thermal conductivity follows nano-structure model as well as alloy scattering. Transmission electron microscopy images shows that there are numerous nano-scale precipitates in a matrix. Owing to the low thermal conductivity and high power factor, we report high thermoelectric performances such as the high ZT, engineering ZTeng , efficiency η.
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22
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Luo J, You L, Zhang J, Guo K, Zhu H, Gu L, Yang Z, Li X, Yang J, Zhang W. Enhanced Average Thermoelectric Figure of Merit of the PbTe-SrTe-MnTe Alloy. ACS Appl Mater Interfaces 2017; 9:8729-8736. [PMID: 28256136 DOI: 10.1021/acsami.6b16060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Thermoelectric properties of Na-doped PbTe-SrTe system have been improved by the addition of Mn. The substitution of Mn for Pb modifies the band structure of the PbTe-SrTe alloy, which enlarges the band gap and increases the valence band degeneracy. This leads to increased thermopowers and power factors near room temperature, and the electronic contribution to the total thermal conductivity is also substantially reduced due to increased resistivity. Moreover, alloying of MnTe within the PbTe matrix introduces low angle grain boundaries, and significantly reduces the lattice thermal conductivity due to the dislocation scattering. A thermoelectric figure of merit as high as 1.98 and an enhancement of the average thermoelectric figure of merit by 18% are achieved for the sample with 4 at% Mn with respect to the Mn-free sample, which can be mainly attributed to the synergistic effects of the band structure modification and the dislocation scattering on phonon transport, both induced by alloying with MnTe. Our experimental results demonstrate the promising potential of PbTe-SrTe-MnTe system for the application of waste heat recovery.
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Affiliation(s)
- Jun Luo
- School of Materials Science and Engineering, Shanghai University , 99 Shangda Road, Shanghai 200444, China
- Materials Genome Institute, Shanghai University , 99 Shangda Road, Shanghai 200444, China
| | - Li You
- School of Materials Science and Engineering, Shanghai University , 99 Shangda Road, Shanghai 200444, China
| | - Jiye Zhang
- School of Materials Science and Engineering, Shanghai University , 99 Shangda Road, Shanghai 200444, China
| | - Kai Guo
- School of Materials Science and Engineering, Shanghai University , 99 Shangda Road, Shanghai 200444, China
| | - Hangtian Zhu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China
| | - Lin Gu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter , Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences , Beijing 100190, China
| | - Zhenzhong Yang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China
| | - Xin Li
- Materials Genome Institute, Shanghai University , 99 Shangda Road, Shanghai 200444, China
| | - Jiong Yang
- Materials Genome Institute, Shanghai University , 99 Shangda Road, Shanghai 200444, China
| | - Wenqing Zhang
- School of Materials Science and Engineering, Shanghai University , 99 Shangda Road, Shanghai 200444, China
- Materials Genome Institute, Shanghai University , 99 Shangda Road, Shanghai 200444, China
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23
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Eliseev AA, Falaleev NS, Verbitskiy NI, Volykhov AA, Yashina LV, Kumskov AS, Zhigalina VG, Vasiliev AL, Lukashin AV, Sloan J, Kiselev NA. Size-Dependent Structure Relations between Nanotubes and Encapsulated Nanocrystals. Nano Lett 2017; 17:805-810. [PMID: 28005367 DOI: 10.1021/acs.nanolett.6b04031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The structural organization of compounds in a confined space of nanometer-scale cavities is of fundamental importance for understanding the basic principles for atomic structure design at the nanolevel. Here, we explore size-dependent structure relations between one-dimensional PbTe nanocrystals and carbon nanotube containers in the diameter range of 2.0-1.25 nm using high-resolution transmission electron microscopy and ab initio calculations. Upon decrease of the confining volume, one-dimensional crystals reveal gradual thinning, with the structure being cut from the bulk in either a <110> or a <100> growth direction until a certain limit of ∼1.3 nm. This corresponds to the situation when a stoichiometric (uncharged) crystal does not fit into the cavity dimensions. As a result of the in-tube charge compensation, one-dimensional superstructures with nanometer-scale atomic density modulations are formed by a periodic addition of peripheral extra atoms to the main motif. Structural changes in the crystallographic configuration of the composites entail the redistribution of charge density on single-walled carbon nanotube walls and the possible appearance of the electron density wave. The variation of the potential attains 0.4 eV, corresponding to charge density fluctuations of 0.14 e/atom.
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Affiliation(s)
| | | | | | - Andrei A Volykhov
- Kurnakov Institute of General and Inorganic Chemistry RAS , 119991 Moscow, Russia
| | | | - Andrei S Kumskov
- Shubnikov Institute of Crystallography RAS , 119333 Moscow, Russia
- NRC Kurchatov Institute , 123182 Moscow, Russia
| | | | | | | | - Jeremy Sloan
- Department of Physics, University of Warwick , Coventry, Warwickshire CV47AL, U.K
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Ahn K, Shin H, Im J, Park SH, Chung I. ZnTe Alloying Effect on Enhanced Thermoelectric Properties of p-Type PbTe. ACS Appl Mater Interfaces 2017; 9:3766-3773. [PMID: 28051844 DOI: 10.1021/acsami.6b15295] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We investigate the effect of ZnTe incorporation on PbTe to enhance thermoelectric performance. We report structural, microscopic, and spectroscopic characterizations, ab initio theoretical calculations, and thermoelectric transport properties of Pb0.985Na0.015Te-x% ZnTe (x = 0, 1, 2, 4). We find that the solid solubility limit of ZnTe in PbTe is less than 1 mol %. The introduction of 2% ZnTe in p-type Pb0.985Na0.015Te reduces the lattice thermal conductivity through the ZnTe precipitates at the microscale. Consequently, a maximum thermoelectric figure of merit (ZT) of 1.73 at 700 K is achieved for the spark plasma-sintered Pb0.985Na0.015Te-2% ZnTe, which arises from a decreased lattice thermal conductivity of ∼0.69 W m-1 K-1 at ∼700 K in comparison with Pb0.985Na0.015Te.
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Affiliation(s)
- Kyunghan Ahn
- School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University , Seoul 08826, Republic of Korea
| | - Hocheol Shin
- Center for Nanoparticle Research, Institute for Basic Science (IBS) , Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University , Seoul 08826, Republic of Korea
| | - Jino Im
- Thin Film Materials Research Center, Korea Research Institute of Chemical Technology , Daejeon 34114, Republic of Korea
| | - Sang Hyun Park
- Advanced Materials and Devices Laboratory, Korea Institute of Energy Research , Daejeon 34129, Republic of Korea
| | - In Chung
- Center for Nanoparticle Research, Institute for Basic Science (IBS) , Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University , Seoul 08826, Republic of Korea
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Mohanraman R, Lan TW, Hsiung TC, Amada D, Lee PC, Ou MN, Chen YY. Engineering Nanostructural Routes for Enhancing Thermoelectric Performance: Bulk to Nanoscale. Front Chem 2016; 3:63. [PMID: 26913280 PMCID: PMC4753533 DOI: 10.3389/fchem.2015.00063] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 10/20/2015] [Indexed: 11/18/2022] Open
Abstract
Thermoelectricity is a very important phenomenon, especially its significance in heat-electricity conversion. If thermoelectric devices can be effectively applied to the recovery of the renewable energies, such as waste heat and solar energy, the energy shortage, and global warming issues may be greatly relieved. This review focusses recent developments on the thermoelectric performance of a low-dimensional material, bulk nanostructured materials, conventional bulk materials etc. Particular emphasis is given on, how the nanostructure in nanostructured composites, confinement effects in one-dimensional nanowires and doping effects in conventional bulk composites plays an important role in ZT enhancement.
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Affiliation(s)
- Rajeshkumar Mohanraman
- Department of Engineering and System Science, National Tsing Hua UniversityHsinchu, Taiwan; Institute of Physics, Academia SinicaTaipei, Taiwan; Nano Science and Technology, Taiwan International Graduate Program, Institute of Physics, Academia SinicaTaipei, Taiwan
| | - Tian-Wey Lan
- Institute of Physics, Academia SinicaTaipei, Taiwan; Nano Science and Technology, Taiwan International Graduate Program, Institute of Physics, Academia SinicaTaipei, Taiwan; Department of Physics, National Taiwan UniversityTaipei, Taiwan
| | - Te-Chih Hsiung
- Institute of Physics, Academia SinicaTaipei, Taiwan; Nano Science and Technology, Taiwan International Graduate Program, Institute of Physics, Academia SinicaTaipei, Taiwan; Department of Physics, National Taiwan UniversityTaipei, Taiwan
| | - Dedi Amada
- Research Center for Electronics and Telecommunication, Indonesian Institutes of Sciences Badung, Indonesia
| | | | - Min-Nan Ou
- Institute of Physics, Academia Sinica Taipei, Taiwan
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Yang H, Bahk JH, Day T, Mohammed AMS, Snyder GJ, Shakouri A, Wu Y. Enhanced thermoelectric properties in bulk nanowire heterostructure-based nanocomposites through minority carrier blocking. Nano Lett 2015; 15:1349-55. [PMID: 25574778 DOI: 10.1021/nl504624r] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
To design superior thermoelectric materials the minority carrier blocking effect in which the unwanted bipolar transport is prevented by the interfacial energy barriers in the heterogeneous nanostructures has been theoretically proposed recently. The theory predicts an enhanced power factor and a reduced bipolar thermal conductivity for materials with a relatively low doping level, which could lead to an improvement in the thermoelectric figure of merit (ZT). Here we show the first experimental demonstration of the minority carrier blocking in lead telluride-silver telluride (PbTe-Ag2Te) nanowire heterostructure-based nanocomposites. The nanocomposites are made by sintering PbTe-Ag2Te nanowire heterostructures produced in a highly scalable solution-phase synthesis. Compared with Ag2Te nanowire-based nanocomposite produced in similar method, the PbTe-Ag2Te nanocomposite containing ∼5 atomic % PbTe exhibits enhanced Seebeck coefficient, reduced thermal conductivity, and ∼40% improved ZT, which can be well explained by the theoretical modeling based on the Boltzmann transport equations when energy barriers for both electrons and holes at the heterostructure interfaces are considered in the calculations. For this p-type PbTe-Ag2Te nanocomposite, the barriers for electrons, that is, minority carriers, are primarily responsible for the ZT enhancement. By extending this approach to other nanostructured systems, it represents a key step toward low-cost solution-processable nanomaterials without heavy doping level for high-performance thermoelectric energy harvesting.
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Affiliation(s)
- Haoran Yang
- School of Chemical Engineering and ‡Birck Nanotechnology Center, Purdue University , West Lafayette, Indiana 47907, United States
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Njegic B, Levin EM, Schmidt-Rohr K. 125Te NMR chemical-shift trends in PbTe-GeTe and PbTe-SnTe alloys. Solid State Nucl Magn Reson 2013; 55-56:79-83. [PMID: 24148972 DOI: 10.1016/j.ssnmr.2013.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 09/26/2013] [Accepted: 09/27/2013] [Indexed: 06/02/2023]
Abstract
Complex tellurides, such as doped PbTe, GeTe, and their alloys, are among the best thermoelectric materials. Knowledge of the change in (125)Te NMR chemical shift due to bonding to dopant or "solute" atoms is useful for determination of phase composition, peak assignment, and analysis of local bonding. We have measured the (125)Te NMR chemical shifts in PbTe-based alloys, Pb1-xGexTe and Pb1-xSnxTe, which have a rocksalt-like structure, and analyzed their trends. For low x, several peaks are resolved in the 22-kHz MAS (125)Te NMR spectra. A simple linear trend in chemical shifts with the number of Pb neighbors is observed. No evidence of a proposed ferroelectric displacement of Ge atoms in a cubic PbTe matrix is detected at low Ge concentrations. The observed chemical shift trends are compared with the results of DFT calculations, which confirm the linear dependence on the composition of the first-neighbor shell. The data enable determination of the composition of various phases in multiphase telluride materials. They also provide estimates of the (125)Te chemical shifts of GeTe and SnTe (+970 and +400±150 ppm, respectively, from PbTe), which are otherwise difficult to access due to Knight shifts of many hundreds of ppm in neat GeTe and SnTe.
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Affiliation(s)
- B Njegic
- Division of Materials Sciences and Engineering, Ames Laboratory U.S. DOE, Ames, IA 50011, USA; Department of Chemistry, Iowa State University, Ames, IA 50011, USA
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Abstract
The use of ultraviolet photoemission to determine the density of valence and conduction states is reviewed. Two approaches are recognized. In one, the photoemission as well as other studies are used to locate experimentally a limited number of features of the band structure. Once these are fixed, band structure calculations could be carried out throughout the zone and checked against other features of the photoemission data. If the agreement is sufficiently good, the density of states is then calculated from the band structure. The second method depends only on experimental data. Using this approach, features of the density of states are determined directly by the photoemission experiment without recourse to band calculations. In cases where bands are wide and k clearly provides an empirically important optical selection rule, this is possible only for portions of the bands which are relatively flat. Successful determinations of this type are cited for PbTe, and GaAs. In metals with narrow d bands such as Cu, it has been found empirically that one may explain fairly well the experimental energy distribution curves in terms of transitions between a density of initial and final states (the optical density of states, ODS) requiring only conservation of energy. The ODS determined by such ultraviolet photoemission studies have more strong detailed structure than the density of states determined by any other experimental method. Studies on a large number of materials indicate that the position in energy of this structure correlates rather well with the position in energy of structure in the calculated density of states. It is suggested, following the very recent theoretical work of Doniach, that k conservation becomes less important (and nondirect transitions more important) as the mass of the hole becomes larger. This is due to the change in k of electrons in states near the Fermi level as they attempt to screen the hole left in the optical excitation process. These electrons take up the excess momentum. One would expect the k conservation selection rule to play an increasingly important role as the mass of the hole decreases. This is in agreement with experiment.
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Affiliation(s)
- W E Spicer
- Stanford Electronic Laboratory, Stanford University, Stanford, California 94305
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