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Mohanta RK, Roy KS, Gupta SP, Yella A, Panchakarla L. Exfoliation of Ca 3Co 4O 9 to Two-Dimensional Single-Crystalline Misfit Calcium Cobaltates for Energy Storage Applications. ACS APPLIED MATERIALS & INTERFACES 2024; 16:19330-19339. [PMID: 38568007 DOI: 10.1021/acsami.3c17160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
Layered materials have become indispensable in the development of two-dimensional (2D) systems, offering extensive specific surface area and exceptional electrical, electrochemical, and optical properties critical for diverse applications in energy storage, catalysis, sensing, and optoelectronics. While mono- and biatomic layered materials have demonstrated remarkable characteristics in lower dimensions, the quest for complexity in materials has opened new avenues for tailoring properties to specific requirements. Within this context, misfit-layered compounds (MLCs) stand out as promising candidates. In this study, we present a successful synthesis of few-layered misfit CaCoO2-CoO2 2D nanosheets in bulk quantities from bulk calcium cobalt oxide (CCO-B or CCO). These newly synthesized 2D exfoliated misfit nanosheets demonstrate remarkable 7-fold electrochemical energy storage properties, surpassing their parent bulk CCO, as cathode materials in aqueous Zn-ion batteries. This work addresses the longstanding challenge of exfoliating bulk MLCs to nanostructured, lower dimensional MLCs, opening doors for utilization in advanced energy storage systems and beyond.
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Affiliation(s)
- Rajat Kumar Mohanta
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Kankona Singha Roy
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Shobhnath P Gupta
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Aswani Yella
- Department of Metallurgical Engineering & Materials Science, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Leela Panchakarla
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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2
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Kang Y, Tan Y, Zhang R, Xie X, Hua W. In-Situ Chemical Thinning and Surface Doping of Layered Bi 2Se 3. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3725. [PMID: 36364501 PMCID: PMC9658795 DOI: 10.3390/nano12213725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 10/20/2022] [Accepted: 10/21/2022] [Indexed: 06/16/2023]
Abstract
As a promising topological insulator, two-dimensional (2D) bismuth selenide (Bi2Se3) attracts extensive research interest. Controllable surface doping of layered Bi2Se3 becomes a crucial issue for the relevant applications. Here, we propose an efficient method for the chemical thinning and surface doping of layered Bi2Se3, forming Se/Bi2Se3 heterostructures with tunable thickness ranging from a few nanometers to hundreds of nanometers. The thickness can be regulated by varying the reaction time and large-size few-layer Bi2Se3 sheets can be obtained. Different from previous liquid-exfoliation methods that require complex reaction process, in-situ and thickness-controllable exfoliation of large-size layered Bi2Se3 can be realized via the developed method. Additionally, the formation of Se nanomeshes coated on the Bi2Se3 sheets remarkably enhance the intensity of Raman vibration peaks, indicating that this method can be used for surface-enhanced Raman scattering. The proposed chemical thinning and surface-doping method is expected to be extended to other bulk-layered materials for high-efficient preparation of 2D heterostructures.
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Affiliation(s)
- Yan Kang
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
| | - Yinlong Tan
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
| | - Renyan Zhang
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
| | - Xiangnan Xie
- College of Computer Science and Technology, National University of Defense Technology, Changsha 410073, China
| | - Weihong Hua
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
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3
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Yakovlev DS, Lvov DS, Emelyanova OV, Dzhumaev PS, Shchetinin IV, Skryabina OV, Egorov SV, Ryazanov VV, Golubov AA, Roditchev D, Stolyarov VS. Physical Vapor Deposition Features of Ultrathin Nanocrystals of Bi 2(Te xSe 1-x) 3. J Phys Chem Lett 2022; 13:9221-9231. [PMID: 36170663 DOI: 10.1021/acs.jpclett.2c02664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Structural and electronic properties of ultrathin nanocrystals of chalcogenide Bi2(Tex Se1-x)3 were studied. The nanocrystals were formed from the parent compound Bi2Te2Se on as-grown and thermally oxidized Si(100) substrates using Ar-assisted physical vapor deposition, resulting in well-faceted single crystals several quintuple layers thick and a few hundreds nanometers large. The chemical composition and structure of the nanocrystals were analyzed by energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, electron backscattering, and X-ray diffraction. The electron transport through nanocrystals connected to superconducting Nb electrodes demonstrated Josephson behavior, with the predominance of the topological channels [Stolyarov et al. Commun. Mater., 2020, 1, 38]. The present paper focuses on the effect of the growth conditions on the morphology, structural, and electronic properties of nanocrystals.
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Affiliation(s)
- Dmitry S Yakovlev
- Center for Advanced Mesoscience and Nanotechnology, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700, Russia
- Russian Quantum Center, Skolkovo, Moscow Region 143025, Russia
| | - Dmitry S Lvov
- Institute of Solid State Physics RAS, Chernogolovka, Moscow Region 142432, Russia
| | | | - Pave S Dzhumaev
- National Research Nuclear University MEPhI, Moscow 115409, Russia
| | - Igor V Shchetinin
- National University of Science and Technology MISIS, Moscow 119049, Russia
| | - Olga V Skryabina
- Center for Advanced Mesoscience and Nanotechnology, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700, Russia
- Institute of Solid State Physics RAS, Chernogolovka, Moscow Region 142432, Russia
- National University of Science and Technology MISIS, Moscow 119049, Russia
| | - Sergey V Egorov
- Russian Quantum Center, Skolkovo, Moscow Region 143025, Russia
- Institute of Solid State Physics RAS, Chernogolovka, Moscow Region 142432, Russia
| | - Valery V Ryazanov
- Russian Quantum Center, Skolkovo, Moscow Region 143025, Russia
- Institute of Solid State Physics RAS, Chernogolovka, Moscow Region 142432, Russia
- National University of Science and Technology MISIS, Moscow 119049, Russia
| | - Alexander A Golubov
- Faculty of Science and Technology, MESA+ Institute of Nanotechnology, Enschede 7500 AE, The Netherlands
| | - Dimitri Roditchev
- Laboratoire de Physique et d'Étude des Matériaux (LPEM), UMR-8213, ESPCI Paris, PSL Research University, CNRS, Sorbonne Université, Paris 75005, France
| | - Vasily S Stolyarov
- Center for Advanced Mesoscience and Nanotechnology, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700, Russia
- National University of Science and Technology MISIS, Moscow 119049, Russia
- Dukhov Research Institute of Automatics (VNIIA), Moscow 127055, Russia
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Rasche B, Brunner J, Schramm T, Ghimire MP, Nitzsche U, Büchner B, Giraud R, Richter M, Dufouleur J. Determination of Cleavage Energy and Efficient Nanostructuring of Layered Materials by Atomic Force Microscopy. NANO LETTERS 2022; 22:3550-3556. [PMID: 35427144 DOI: 10.1021/acs.nanolett.1c04868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A method is presented to use atomic force microscopy to measure the cleavage energy of van der Waals materials and similar quasi-two-dimensional materials. The cleavage energy of graphite is measured to be 0.36 J/m2, in good agreement with literature data. The same method yields a cleavage energy of 0.6 J/m2 for MoS2 as a representative of the dichalcogenides. In the case of the weak topological insulator Bi14Rh3I9 no cleavage energy is obtained, although cleavage is successful with an adapted approach. The cleavage energies of these materials are evaluated by means of density-functional calculations and literature data. This further validates the presented method and sets an upper limit of about 0.7 J/m2 to the cleavage energy that can be measured by the present setup. In addition, this method can be used as a tool for manipulating exfoliated flakes, prior to or after contacting, which may open a new route for the fabrication of nanostructures.
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Affiliation(s)
- Bertold Rasche
- Department of Chemistry, University of Cologne, 50939 Cologne, Germany
| | - Julius Brunner
- Leibniz IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany
| | - Tim Schramm
- Leibniz IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany
| | - Madhav Prasad Ghimire
- Central Department of Physics, Tribhuvan University, Kirtipur 44613, Kathmandu, Nepal
| | - Ulrike Nitzsche
- Leibniz IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany
| | - Bernd Büchner
- Leibniz IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany
- Department of Physics, TU Dresden, D-01062 Dresden, Germany
| | - Romain Giraud
- Leibniz IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany
- Université Grenoble Alpes, CNRS, CEA, Grenoble-INP, Spintec, F-38000 Grenoble, France
| | - Manuel Richter
- Leibniz IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany
- Dresden Center for Computational Materials Science (DCMS), TU Dresden, D-01062 Dresden, Germany
| | - Joseph Dufouleur
- Leibniz IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany
- Center for Transport and Devices, TU Dresden, D-01062 Dresden, Germany
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5
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Yu T, Luo R, Wang T, Zhang D, Liu W, Yu T, Liao Q. Enhancement of Casimir Friction between Graphene-Covered Topological Insulator. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:1148. [PMID: 35407266 PMCID: PMC9000827 DOI: 10.3390/nano12071148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 03/14/2022] [Accepted: 03/28/2022] [Indexed: 11/26/2022]
Abstract
Casimir friction is theoretically studied between graphene-covered undoped bismuth selenide (Bi2Se3) in detail. In the graphene/Bi2Se3 composite structure, the coupling of the hyperbolic phonon polaritons supported by Bi2Se3 with the surface plasmons supported by graphene can lead to the hybrid surface plasmon-phonon polaritons (SPPPs). Compared with that between undoped Bi2Se3, Casimir friction can be enhanced by more than one order of magnitude due to the contribution of SPPPs. It is found that the chemical potential that can be used to modulate the optical characteristic of SPPPs plays an important role in Casimir friction. In addition, the Casimir friction between doped Bi2Se3 is also studied. The friction coefficient between doped Bi2Se3 can even be larger than that between graphene-covered undoped Bi2Se3 for suitable chemical potential due to the contribution of unusual electron surface states. The results obtained in this work are not only beneficial to the study of Casimir frictions but also extend the research ranges of topological insulators.
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Affiliation(s)
| | | | - Tongbiao Wang
- Department of Physics, Nanchang University, Nanchang 330031, China; (T.Y.); (R.L.); (D.Z.); (W.L.); (T.Y.); (Q.L.)
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6
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Zhao Y, Lu Y, Li H, Zhu Y, Meng Y, Li N, Wang D, Jiang F, Mo F, Long C, Guo Y, Li X, Huang Z, Li Q, Ho JC, Fan J, Sui M, Chen F, Zhu W, Liu W, Zhi C. Few-layer bismuth selenide cathode for low-temperature quasi-solid-state aqueous zinc metal batteries. Nat Commun 2022; 13:752. [PMID: 35136082 PMCID: PMC8825835 DOI: 10.1038/s41467-022-28380-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Accepted: 01/19/2022] [Indexed: 12/02/2022] Open
Abstract
The performances of rechargeable batteries are strongly affected by the operating environmental temperature. In particular, low temperatures (e.g., ≤0 °C) are detrimental to efficient cell cycling. To circumvent this issue, we propose a few-layer Bi2Se3 (a topological insulator) as cathode material for Zn metal batteries. When the few-layer Bi2Se3 is used in combination with an anti-freeze hydrogel electrolyte, the capacity delivered by the cell at −20 °C and 1 A g−1 is 1.3 larger than the capacity at 25 °C for the same specific current. Also, at 0 °C the Zn | |few-layer Bi2Se3 cell shows capacity retention of 94.6% after 2000 cycles at 1 A g−1. This behaviour is related to the fact that the Zn-ion uptake in the few-layer Bi2Se3 is higher at low temperatures, e.g., almost four Zn2+ at 25 °C and six Zn2+ at −20 °C. We demonstrate that the unusual performance improvements at low temperatures are only achievable with the few-layer Bi2Se3 rather than bulk Bi2Se3. We also show that the favourable low-temperature conductivity and ion diffusion capability of few-layer Bi2Se3 are linked with the presence of topological surface states and weaker lattice vibrations, respectively. The performances of rechargeable batteries are detrimentally affected by low temperatures (e.g., < 0 °C). Here, the authors report a few-layer Bi2Se3 material capable of improving battery cycling performances when operational temperatures are shifted from +25 °C to −20 °C.
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Affiliation(s)
- Yuwei Zhao
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
| | - Yue Lu
- Institute of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing, China
| | - Huiping Li
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, Department of Physics, University of Science and Technology of China, Hefei, China
| | - Yongbin Zhu
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, China
| | - You Meng
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
| | - Na Li
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
| | - Donghong Wang
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
| | - Feng Jiang
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, China
| | - Funian Mo
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
| | - Changbai Long
- School of Advanced Materials and Nanotechnology, Xidian University, Xi'an, China
| | - Ying Guo
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
| | - Xinliang Li
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
| | - Zhaodong Huang
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
| | - Qing Li
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
| | - Johnny C Ho
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
| | - Jun Fan
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
| | - Manling Sui
- Institute of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing, China
| | - Furong Chen
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China
| | - Wenguang Zhu
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, Department of Physics, University of Science and Technology of China, Hefei, China.
| | - Weishu Liu
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, China.
| | - Chunyi Zhi
- Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China. .,Centre for Functional Photonics, City University of Hong Kong, Kowloon, Hong Kong.
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7
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Abstract
2D layered materials with diverse exciting properties have recently attracted tremendous interest in the scientific community. Layered topological insulator Bi2Se3 comes into the spotlight as an exotic state of quantum matter with insulating bulk states and metallic Dirac-like surface states. Its unique crystal and electronic structure offer attractive features such as broadband optical absorption, thickness-dependent surface bandgap and polarization-sensitive photoresponse, which enable 2D Bi2Se3 to be a promising candidate for optoelectronic applications. Herein, we present a comprehensive summary on the recent advances of 2D Bi2Se3 materials. The structure and inherent properties of Bi2Se3 are firstly described and its preparation approaches (i.e., solution synthesis and van der Waals epitaxy growth) are then introduced. Moreover, the optoelectronic applications of 2D Bi2Se3 materials in visible-infrared detection, terahertz detection, and opto-spintronic device are discussed in detail. Finally, the challenges and prospects in this field are expounded on the basis of current development.
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Affiliation(s)
- Fakun K. Wang
- State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Sijie J. Yang
- State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Tianyou Y. Zhai
- State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
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8
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Dedi, Lee PC, Wei PC, Chen YY. Thermoelectric Characteristics of A Single-Crystalline Topological Insulator Bi 2Se 3 Nanowire. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:819. [PMID: 33806921 PMCID: PMC8005119 DOI: 10.3390/nano11030819] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 03/19/2021] [Accepted: 03/20/2021] [Indexed: 11/16/2022]
Abstract
The discovery of topological insulators (TIs) has motivated detailed studies on their physical properties, especially on their novel surface states via strong spin-orbit interactions. However, surface-state-related thermoelectric properties are rarely reported, likely because of the involvement of their bulk-dominating contribution. In this work, we report thermoelectric studies on a TI bismuth selenide (Bi2Se3) nanowire (NW) that exhibit a larger surface/volume ratio. Uniform single-crystalline TI Bi2Se3 NWs were successfully synthesized using a stress-induced growth method. To achieve the study of the thermoelectric properties of a nanowire (NW), including electrical conductivity (σ), Seebeck coefficient (S), and thermal conductivity (κ), a special platform for simultaneously performing all measurements on a single wire was designed. The properties of σ, S, and κ of a 200 nm NW that was well precharacterized using transmission electron microscope (TEM) measurements were determined using the four-probe method, the two-probe EMF across ∇T measurement, and the 3ω technique, respectively. The integrated TE properties represented by the figure of merit ZT (S2σT/κ) were found to be in good agreement with a theoretical study of Bi2Se3 NW.
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Affiliation(s)
- Dedi
- Research Center for Electronics and Telecommunications (P2ET), Indonesian Institute of Sciences (LIPI), Bandung 40135, Indonesia
- Institute of Physics, Academia Sinica, Taipei 11529, Taiwan; (P.-C.L.); (Y.-Y.C.)
| | - Ping-Chung Lee
- Institute of Physics, Academia Sinica, Taipei 11529, Taiwan; (P.-C.L.); (Y.-Y.C.)
| | - Pai-Chun Wei
- Center for Condensed Matter Sciences and Center of Atomic Initiatives for New Materials, National Taiwan University, Taipei 10617, Taiwan;
| | - Yang-Yuan Chen
- Institute of Physics, Academia Sinica, Taipei 11529, Taiwan; (P.-C.L.); (Y.-Y.C.)
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9
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Luo S, Li J, Sun T, Liu X, Wei D, Zhou D, Shen J, Wei D. High-performance mid-infrared photodetection based on Bi 2Se 3 maze and free-standing nanoplates. NANOTECHNOLOGY 2021; 32:105705. [PMID: 33232950 DOI: 10.1088/1361-6528/abcd64] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The pursuit of optoelectronic devices operating in mid-infrared regime is driven by both fundamental interests and commercial applications. The narrow bandgap (0.3 eV) of layered Bi2Se3 makes it a promising material for mid-infrared photodetection. However, the weak absorption of mid-infrared optical power and high dark current level restrict its performance. Here, a supply-control technique is applied to modulate the growth mode of Bi2Se3 crystal, and Bi2Se3 crystals with various morphologies are obtained. The nanoplates pattern transits from maze to freestanding when source mass was tuned. Due to the strong infrared absorption and photoelectric conversion efficiency of vertical Bi2Se3 nanoplates, the as-prepared vertical Bi2Se3 nanoplates/Si heterojunction shows excellent photoresponse and extremely low dark current. Among these devices based on different Bi2Se3 morphologies, freestanding nanoplates show the optimal mid-infrared characteristics, namely a photo-to-dark ratio of 2.0 × 104, a dark current of 0.21 pA, a response time of 23 ms, a specific detectivity of 6.1 × 1010 Jones (calculated) and 1.2 × 1010 Jones (measured) under 2.7 μm illumination and at room temperature. Notably, the specific detectivity of our devices are comparable to commercial InGaAs photodetectors. With the tunable- morphology growing technique and excellent photoresponding characteristics, Bi2Se3 nanomaterials are worth attention in optoelectronic field.
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Affiliation(s)
- Shi Luo
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, People's Republic of China
- State Key Laboratory of Molecular Engineering of Polymers & Department of Macromolecular Science, Fudan University, Shanghai, 200433, People's Republic of China
| | - JiaLu Li
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, People's Republic of China
- Department of Physics, Harbin Institute of Technology, Harbin, 150001, People's Republic of China
| | - Tai Sun
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, People's Republic of China
| | - Xiangzhi Liu
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, People's Republic of China
| | - Dacheng Wei
- State Key Laboratory of Molecular Engineering of Polymers & Department of Macromolecular Science, Fudan University, Shanghai, 200433, People's Republic of China
| | - Dahua Zhou
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, People's Republic of China
| | - Jun Shen
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, People's Republic of China
| | - Dapeng Wei
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, People's Republic of China
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10
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Lê Anh M, Potapov P, Wolf D, Lubk A, Glatz B, Fery A, Doert T, Ruck M. Freestanding Nanolayers of a Wide-Gap Topological Insulator through Liquid-Phase Exfoliation. Chemistry 2021; 27:794-801. [PMID: 33125781 PMCID: PMC7839554 DOI: 10.1002/chem.202004320] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Indexed: 11/11/2022]
Abstract
The layered salt Bi14 Rh3 I9 is a weak three-dimensional (3D) topological insulator (TI), that is, a stack of two-dimensional (2D) TIs. It has a wide non-trivial band gap of 210 meV, which is generated by strong spin-orbit coupling, and possesses protected electronic edge-states. In the structure, charged layers of∞ 2 [ (Bi4 Rh)3 I]2+ honeycombs and∞ 1 [ Bi2 I8 ]2- chains alternate. The non-trivial topology of Bi14 Rh3 I9 is an inherent property of the 2D intermetallic fragment. Here, the exfoliation of Bi14 Rh3 I9 was performed using two different chemical approaches: (a) through a reaction with n-butyllithium and poly(vinylpyrrolidone), (b) through a reaction with betaine in dimethylformamide at 55 °C. The former yielded few-layer sheets of the new compound Bi12 Rh3 I, while the latter led to crystalline sheets of Bi14 Rh3 I9 with a thickness down to 5 nm and edge-lengths up to several ten microns. X-ray diffraction and electron microscopy proved that the structure of Bi14 Rh3 I9 remained intact. Thus, it was assumed that the particles are still TIs. Dispersions of these flakes now allow for next steps towards the envisioned applications in nanoelectronics, such as the study of quantum coherence in deposited films, the combination with superconducting particles or films for the generation of Majorana fermions, or studies on their behavior under the influence of magnetic or electric fields or in contact with various materials occurring in devices. The method presented generally allows to exfoliate layers with high specific charges and thus the use of layered starting materials beyond van der Waals crystals.
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Affiliation(s)
- Mai Lê Anh
- Faculty of Chemistry and Food ChemistryTechnische Universität Dresden01062DresdenGermany
| | | | | | - Axel Lubk
- Leibniz IFW Dresden01069DresdenGermany
- Würzburg-Dresden Cluster of Excellence ct.qmatTechnische Universität Dresden01062DresdenGermany
| | - Bernhard Glatz
- Leibniz Institute of Polymer Research Dresden01069DresdenGermany
| | - Andreas Fery
- Leibniz Institute of Polymer Research Dresden01069DresdenGermany
| | - Thomas Doert
- Faculty of Chemistry and Food ChemistryTechnische Universität Dresden01062DresdenGermany
| | - Michael Ruck
- Faculty of Chemistry and Food ChemistryTechnische Universität Dresden01062DresdenGermany
- Würzburg-Dresden Cluster of Excellence ct.qmatTechnische Universität Dresden01062DresdenGermany
- Max Planck Institute for Chemical Physics of Solids01187DresdenGermany
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11
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Lazanas AC, Prodromidis MI. Two-dimensional inorganic nanosheets: production and utility in the development of novel electrochemical (bio)sensors and gas-sensing applications. Mikrochim Acta 2021; 188:6. [PMID: 33389171 DOI: 10.1007/s00604-020-04674-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 11/30/2020] [Indexed: 01/09/2023]
Abstract
This review (with 178 references) focuses on inorganic layered materials (ILMs) and the use of their two-dimensional nanosheets in the development of novel electrochemical (bio)sensors, analytical devices, and gas-phase sensing applications. The text is organized in three main sections including the presentation of the most important families of ILMs, a comprehensive outline of various "bottom-up", "top-down," and hydro(solvo)thermal methods that have been used for the production of ILM nanosheets, and finally an evaluative survey on their utility for the determination of analytes with interest in different sectors of contemporary analysis. Critical discussion on the effect of the production method on their electronic properties, the suitability of each nanomaterial in different sensing technologies along with an assessment of the performance of the (bio)sensors and devices that have been proposed within the last 5 years, is enclosed. The perspectives of further improving the utility of 2D inorganic nanosheets in sensing applications, in real-world samples, are also discussed.
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Affiliation(s)
- Alexandros Ch Lazanas
- Laboratory of Analytical Chemistry, Department of Chemistry, University of Ioannina, 45 110, Ioannina, Greece
| | - Mamas I Prodromidis
- Laboratory of Analytical Chemistry, Department of Chemistry, University of Ioannina, 45 110, Ioannina, Greece.
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12
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Deng X, Li Z. Intrinsic ferromagnetic semiconductivity realized in a new MoS 2 monolayer. Phys Chem Chem Phys 2020; 22:13363-13367. [PMID: 32531005 DOI: 10.1039/c9cp05804d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Magnetic semiconductors, with semiconductivity and ferromagnetism simultaneously, have promising important applications as storage devices. However, the ordered ferromagnetic state easily suffers from enhanced thermal fluctuation, inducing a very small Curie temperature. Here we have successfully predicted a new 2D small-gap MoS2 magnetic semiconductor. Instead, almost all of the reported MoS2 phase was nonmagnetic whether it exhibited semiconducting or metal behavior. Monte Carlo simulations showed that its Curie temperature could approach 130 K and could be further enhanced through applying biaxial tensile strain. The revealed atomic bonding pattern paves a new way to explore novel electronic and magnetic materials.
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Affiliation(s)
- Xiaohui Deng
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
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13
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Zhang P, Yang S, Pineda-Gómez R, Ibarlucea B, Ma J, Lohe MR, Akbar TF, Baraban L, Cuniberti G, Feng X. Electrochemically Exfoliated High-Quality 2H-MoS 2 for Multiflake Thin Film Flexible Biosensors. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2019; 15:e1901265. [PMID: 31034144 DOI: 10.1002/smll.201901265] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 04/13/2019] [Indexed: 06/09/2023]
Abstract
2D molybdenum disulfide (MoS2 ) gives a new inspiration for the field of nanoelectronics, photovoltaics, and sensorics. However, the most common processing technology, e.g., liquid-phase based scalable exfoliation used for device fabrication, leads to the number of shortcomings that impede their large area production and integration. Major challenges are associated with the small size and low concentration of MoS2 flakes, as well as insufficient control over their physical properties, e.g., internal heterogeneity of the metallic and semiconducting phases. Here it is demonstrated that large semiconducting MoS2 sheets (with dimensions up to 50 µm) can be obtained by a facile cathodic exfoliation approach in nonaqueous electrolyte. The synthetic process avoids surface oxidation thus preserving the MoS2 sheets with intact crystalline structure. It is further demonstrated at the proof-of-concept level, a solution-processed large area (60 × 60 µm) flexible Ebola biosensor, based on a MoS2 thin film (6 µm thickness) fabricated via restacking of the multiple flakes on the polyimide substrate. The experimental results reveal a low detection limit (in femtomolar-picomolar range) of the fabricated sensor devices. The presented exfoliation method opens up new opportunities for fabrication of large arrays of multifunctional biomedical devices based on novel 2D materials.
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Affiliation(s)
- Panpan Zhang
- Chair for Molecular Functional Materials, Department of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstr. 4, 01069, Dresden, Germany
- Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany
| | - Sheng Yang
- Chair for Molecular Functional Materials, Department of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstr. 4, 01069, Dresden, Germany
- Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany
| | - Roberto Pineda-Gómez
- Max Bergman Center of Biomaterials Dresden and Institute for Materials Science, Technische Universität Dresden, 01062, Dresden, Germany
| | - Bergoi Ibarlucea
- Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany
- Max Bergman Center of Biomaterials Dresden and Institute for Materials Science, Technische Universität Dresden, 01062, Dresden, Germany
| | - Ji Ma
- Chair for Molecular Functional Materials, Department of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstr. 4, 01069, Dresden, Germany
- Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany
| | - Martin R Lohe
- Chair for Molecular Functional Materials, Department of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstr. 4, 01069, Dresden, Germany
- Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany
| | - Teuku Fawzul Akbar
- Max Bergman Center of Biomaterials Dresden and Institute for Materials Science, Technische Universität Dresden, 01062, Dresden, Germany
| | - Larysa Baraban
- Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany
- Max Bergman Center of Biomaterials Dresden and Institute for Materials Science, Technische Universität Dresden, 01062, Dresden, Germany
| | - Gianaurelio Cuniberti
- Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany
- Max Bergman Center of Biomaterials Dresden and Institute for Materials Science, Technische Universität Dresden, 01062, Dresden, Germany
| | - Xinliang Feng
- Chair for Molecular Functional Materials, Department of Chemistry and Food Chemistry, School of Science, Technische Universität Dresden, Mommsenstr. 4, 01069, Dresden, Germany
- Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany
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14
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Solution-Based Synthesis and Processing of Metal Chalcogenides for Thermoelectric Applications. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9071511] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Metal chalcogenide materials are current mainstream thermoelectric materials with high conversion efficiency. This review provides an overview of the scalable solution-based methods for controllable synthesis of various nanostructured and thin-film metal chalcogenides, as well as their properties for thermoelectric applications. Furthermore, the state-of-art ink-based processing method for fabrication of thermoelectric generators based on metal chalcogenides is briefly introduced. Finally, the perspective on this field with regard to material production and device development is also commented upon.
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15
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Zhang R, Fu D, Ni J, Sun C, Song S. Adsorption for SO2 gas molecules on B, N, P and Al doped MoS2: The DFT study. Chem Phys Lett 2019. [DOI: 10.1016/j.cplett.2018.11.054] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Abstract
This review briefly describes the development of synthetic topological insulator materials in the application of advanced electronic devices. As a new class of quantum matter, topological insulators with insulating bulk and conducting surface states have attracted attention in more and more research fields other than condensed matter physics due to their intrinsic physical properties, which provides an excellent basis for novel nanoelectronic, optoelectronic, and spintronic device applications. In comparison to the mechanically exfoliated samples, the newly emerging topological insulator nanostructures prepared with various synthetical approaches are more intriguing because the conduction contribution of the surface states can be significantly enhanced due to the larger surface-to-volume ratio, better manifesting the unique properties of the gapless surface states. So far, these synthetic topological insulator nanostructures have been implemented in different electrically accessible device platforms via electrical, magnetic and optical characterizations for material investigations and device applications, which will be introduced in this review.
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17
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Unexplored photoluminescence from bulk and mechanically exfoliated few layers of Bi 2Te 3. Sci Rep 2018; 8:9205. [PMID: 29907865 PMCID: PMC6004008 DOI: 10.1038/s41598-018-27549-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 06/05/2018] [Indexed: 11/25/2022] Open
Abstract
We report the exotic photoluminescence (PL) behaviour of 3D topological insulator Bi2Te3 single crystals grown by customized self-flux method and mechanically exfoliated few layers (18 ± 2 nm)/thin flakes obtained by standard scotch tape method from as grown Bi2Te3 crystals. The experimental PL studies on bulk single crystal and mechanically exfoliated few layers of Bi2Te3 evidenced a broad red emission in the visible region from 600–690 nm upon 375 nm excitation wavelength corresponding to optical band gap of 2 eV. These findings are in good agreement with our theoretical results obtained using the ab initio density functional theory framework. Interestingly, the observed optical band gap is several times larger than the known electronic band gap of ~0.15 eV. The experimentally observed 2 eV optical band gap in the visible region for bulk as well as for mechanically exfoliated few layers Bi2Te3 single crystals clearly rules out the quantum confinement effects in the investigated samples which are well known in the 2D systems like MoS2,WS2, WSe2, and MoSe2 for 1–3 layers.
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18
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Solution Growth of Two-Dimensional Bi₂Se₃ Nanosheets for Two-Color All-Optical Switching. MATERIALS 2017; 10:ma10111332. [PMID: 29160803 PMCID: PMC5706279 DOI: 10.3390/ma10111332] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 11/14/2017] [Accepted: 11/18/2017] [Indexed: 11/24/2022]
Abstract
Two-dimensional Bi2Se3 nanosheets with hexagonal shape are synthesized by a solution synthetic route. The Bi2Se3 nanosheets are 120 nm in edge width and 7 nm in thickness. The size of the Bi2Se3 nanosheets can be controlled by choosing different kinds of reducing agents including hydroxylamine and ethylenediamine. Subsequently, we demonstrate a configuration of two-color all-optical switching based on plasma channels effect using the as-synthesized Bi2Se3 nanosheets as an optical media. The signal light can be modulated as two states including dot and ring shape by changing the intensity of control light. The modulated signal light exhibits excellent spatial propagation properties. As a type of interesting optical material, ultrathin two-dimensional Bi2Se3 nanosheets might provide an effective option for photoelectric applications.
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Burman D, Ghosh R, Santra S, Kumar Ray S, Kumar Guha P. Role of vacancy sites and UV-ozone treatment on few layered MoS 2 nanoflakes for toxic gas detection. NANOTECHNOLOGY 2017; 28:435502. [PMID: 28832016 DOI: 10.1088/1361-6528/aa87cd] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Various issues like global warming and environmental pollutions have led to the research of toxic gas detection worldwide. In this work, we have tried to develop a molybdenum disulfide (MoS2) based gas sensor to detect toxic gases like ammonia and NO. MoS2, an inorganic analog of graphene, has attracted lots of attention for many different applications recently. This paper reports the use of liquid exfoliated MoS2 nanoflakes as the sensing layer in a handheld, resistive toxic gas sensor. The nanoflakes were exfoliated from MoS2 bulk powder using a sonication based exfoliation technique at room temperature. The successful exfoliation of the nanoflakes was characterized using different techniques e.g., optical microscopy, atomic force microscopy, field emission scanning electron microscopy, high resolution transmission electron microscopy, x-ray diffraction, Raman spectroscopy, x-ray photoelectron spectroscopy and ultraviolet-visible spectrophotometry. The characterization results showed that few-layered nanoflakes have successfully been exfoliated. The MoS2 nanoflakes showed reasonable sensing towards ammonia and NO. In order to explore the effect of particle size on ammonia sensing, the MoS2 flakes were also exfoliated using different sonication times. We also observed that various factors like presence of vacancy sites, ambient oxygen, humidity, different contact electrodes have significant effect on the sensing characteristics. In fact, the response of the sensing layer against 400 ppm of ammonia increased from 54.1% to ∼80% when it was UV-ozone treated. This work holds promises to developing cost-effective, reliable and highly sensitive MoS2 based ammonia sensors.
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Affiliation(s)
- Debasree Burman
- Department of Electronics & Electrical Communication Engineering, IIT Kharagpur, 721302, India
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20
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Tian W, Yu W, Shi J, Wang Y. The Property, Preparation and Application of Topological Insulators: A Review. MATERIALS (BASEL, SWITZERLAND) 2017; 10:E814. [PMID: 28773173 PMCID: PMC5551857 DOI: 10.3390/ma10070814] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 07/09/2017] [Accepted: 07/10/2017] [Indexed: 01/14/2023]
Abstract
Topological insulator (TI), a promising quantum and semiconductor material, has gapless surface state and narrow bulk band gap. Firstly, the properties, classifications and compounds of TI are introduced. Secondly, the preparation and doping of TI are assessed. Some results are listed. (1) Although various preparation methods are used to improve the crystal quality of the TI, it cannot reach the industrialization. Fermi level regulation still faces challenges; (2) The carrier type and lattice of TI are affected by non-magnetic impurities. The most promising property is the superconductivity at low temperature; (3) Magnetic impurities can destroy the time-reversal symmetry of the TI surface, which opens the band gap on the TI surface resulting in some novel physical effects such as quantum anomalous Hall effect (QAHE). Thirdly, this paper summarizes various applications of TI including photodetector, magnetic device, field-effect transistor (FET), laser, and so on. Furthermore, many of their parameters are compared based on TI and some common materials. It is found that TI-based devices exhibit excellent performance, but some parameters such as signal to noise ratio (S/N) are still lower than other materials. Finally, its advantages, challenges and future prospects are discussed. Overall, this paper provides an opportunity to improve crystal quality, doping regulation and application of TI.
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Affiliation(s)
- Wenchao Tian
- School of Electro-Mechanical Engineering, Xidian University, Number 2 Taibai South Road, Xi'an 710071, China.
| | - Wenbo Yu
- School of Electro-Mechanical Engineering, Xidian University, Number 2 Taibai South Road, Xi'an 710071, China.
| | - Jing Shi
- School of Electro-Mechanical Engineering, Xidian University, Number 2 Taibai South Road, Xi'an 710071, China.
| | - Yongkun Wang
- School of Electro-Mechanical Engineering, Xidian University, Number 2 Taibai South Road, Xi'an 710071, China.
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21
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Tseliou F, Avgeropoulos A, Falaras P, Prodromidis MI. Low dimensional Bi 2 Te 3 -graphene oxide hybrid film-modified electrodes for ultra-sensitive stripping voltammetric detection of Pb(II) and Cd(II). Electrochim Acta 2017. [DOI: 10.1016/j.electacta.2017.02.058] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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22
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Gehring P, Reusch FB, Mashhadi SS, Burghard M, Kern K. Surface oxidation effect on the electrical behaviour of Bi2Te2Se nanoplatelets. NANOTECHNOLOGY 2016; 27:285201. [PMID: 27257792 DOI: 10.1088/0957-4484/27/28/285201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Charge transport in topological insulators is notably influenced by moisture and air in the surrounding environment. At present, however, little is known about the detailed composition of the oxidized surface and its impact on the electrical characteristics of these materials. Here, we investigate the surface oxide formation on the topological insulator Bi2Te2Se (BTS) and how this affects its electrical behavior. While ambient exposure of BTS nanoplatelets predominantly creates surface hydroxyl groups, oxygen plasma treatment yields a compact, few-nanometer thick surface oxide layer. The plasma causes p-type doping, accompanied by a decrease of the effective platelet thickness, the interplay of which is manifested in a resistance maximum as a function of plasma treatment time. It is furthermore demonstrated that the structural integrity of the plasma-derived surface oxide is sufficient to enable its use as a gate insulator layer in combination with a top gate.
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Affiliation(s)
- Pascal Gehring
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart, Germany
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23
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Bera A, Pal K, Muthu DVS, Waghmare UV, Sood AK. Pressure-induced phase transition in Bi2Se3 at 3 GPa: electronic topological transition or not? JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:105401. [PMID: 26881905 DOI: 10.1088/0953-8984/28/10/105401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In recent years, a low pressure transition around P3 GPa exhibited by the A2B3-type 3D topological insulators is attributed to an electronic topological transition (ETT) for which there is no direct evidence either from theory or experiments. We address this phase transition and other transitions at higher pressure in bismuth selenide (Bi2Se3) using Raman spectroscopy at pressure up to 26.2 GPa. We see clear Raman signatures of an isostructural phase transition at P2.4 GPa followed by structural transitions at ∼ 10 GPa and 16 GPa. First-principles calculations reveal anomalously sharp changes in the structural parameters like the internal angle of the rhombohedral unit cell with a minimum in the c/a ratio near P3 GPa. While our calculations reveal the associated anomalies in vibrational frequencies and electronic bandgap, the calculated Z2 invariant and Dirac conical surface electronic structure remain unchanged, showing that there is no change in the electronic topology at the lowest pressure transition.
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Affiliation(s)
- Achintya Bera
- Department of Physics, Indian Institute of Science, Bangalore 560 012, India
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24
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Ye Z, de la Rama LP, Efremov MY, Zuo JM, Allen LH. Approaching the size limit of organometallic layers: synthesis and characterization of highly ordered silver–thiolate lamellae with ultra-short chain lengths. Dalton Trans 2016; 45:18954-18966. [DOI: 10.1039/c6dt03629e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Synthesis of single crystal silver alkanethiolate (any chain length) lamellae with highly ordered chain conformations, interlayer interfaces and intralayer lattices.
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Affiliation(s)
- Zichao Ye
- Department of Materials Science and Engineering
- Frederick-Seitz Materials Research Laboratory
- University of Illinois at Urbana-Champaign
- Urbana
- USA
| | - Lito P. de la Rama
- Department of Materials Science and Engineering
- Frederick-Seitz Materials Research Laboratory
- University of Illinois at Urbana-Champaign
- Urbana
- USA
| | | | - Jian-Min Zuo
- Department of Materials Science and Engineering
- Frederick-Seitz Materials Research Laboratory
- University of Illinois at Urbana-Champaign
- Urbana
- USA
| | - Leslie H. Allen
- Department of Materials Science and Engineering
- Frederick-Seitz Materials Research Laboratory
- University of Illinois at Urbana-Champaign
- Urbana
- USA
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25
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Ma F, Zhou M, Jiao Y, Gao G, Gu Y, Bilic A, Chen Z, Du A. Single Layer Bismuth Iodide: Computational Exploration of Structural, Electrical, Mechanical and Optical Properties. Sci Rep 2015; 5:17558. [PMID: 26626797 PMCID: PMC4667189 DOI: 10.1038/srep17558] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 11/02/2015] [Indexed: 11/21/2022] Open
Abstract
Layered graphitic materials exhibit new intriguing electronic structure and the search for new types of two-dimensional (2D) monolayer is of importance for the fabrication of next generation miniature electronic and optoelectronic devices. By means of density functional theory (DFT) computations, we investigated in detail the structural, electronic, mechanical and optical properties of the single-layer bismuth iodide (BiI3) nanosheet. Monolayer BiI3 is dynamically stable as confirmed by the computed phonon spectrum. The cleavage energy (Ecl) and interlayer coupling strength of bulk BiI3 are comparable to the experimental values of graphite, which indicates that the exfoliation of BiI3 is highly feasible. The obtained stress-strain curve shows that the BiI3 nanosheet is a brittle material with a breaking strain of 13%. The BiI3 monolayer has an indirect band gap of 1.57 eV with spin orbit coupling (SOC), indicating its potential application for solar cells. Furthermore, the band gap of BiI3 monolayer can be modulated by biaxial strain. Most interestingly, interfacing electrically active graphene with monolayer BiI3 nanosheet leads to enhanced light absorption compared to that in pure monolayer BiI3 nanosheet, highlighting its great potential applications in photonics and photovoltaic solar cells.
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Affiliation(s)
- Fengxian Ma
- School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), Gardens Point Campus, QLD 4001, Brisbane, Australia
| | - Mei Zhou
- Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084, People's Republic of China
| | - Yalong Jiao
- School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), Gardens Point Campus, QLD 4001, Brisbane, Australia
| | - Guoping Gao
- School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), Gardens Point Campus, QLD 4001, Brisbane, Australia
| | - Yuantong Gu
- School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), Gardens Point Campus, QLD 4001, Brisbane, Australia
| | - Ante Bilic
- CSIRO Manufacturing, Virtual Nanoscience Lab, Parkville 3052 VIC, Australia
| | - Zhongfang Chen
- Department of Chemistry, Institute for Functional Materials, University of Puerto Rico, San Juan, PR 00931, United States
| | - Aijun Du
- School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), Gardens Point Campus, QLD 4001, Brisbane, Australia
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Andzane J, Kunakova G, Charpentier S, Hrkac V, Kienle L, Baitimirova M, Bauch T, Lombardi F, Erts D. Catalyst-free vapour-solid technique for deposition of Bi2Te3 and Bi2Se3 nanowires/nanobelts with topological insulator properties. NANOSCALE 2015; 7:15935-15944. [PMID: 26365282 DOI: 10.1039/c5nr04574f] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We present a simple two-stage vapour-solid synthesis method for the growth of bismuth chalcogenide (Bi2Te3, Bi2Se3) topological insulator nanowires/nanobelts by using Bi2Se3 or Bi2Te3 powders as source materials. During the first stage of the synthesis process nanoplateteles, serving as "catalysts" for further nanowire/nanobelt growth, are formed. At a second stage of the synthesis, the introduction of a N2 flow at 35 Torr pressure in the chamber induces the formation of free standing nanowires/nanobelts. The synthesised nanostructures demonstrate a layered single-crystalline structure and Bi : Se and Bi : Te ratios 40 : 60 at% for both Bi2Se3 and Bi2Te3 nanowires/nanobelts. The presence of Shubnikov de Haas oscillations in the longitudinal magneto-resistance of the nanowires/nanobelts and their specific angular dependence confirms the existence of 2D topological surface states in the synthesised nanostructures.
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Affiliation(s)
- J Andzane
- Institute of Chemical Physics, University of Latvia, LV-1586, Riga, Latvia.
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27
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Guo Y, Liu Z, Peng H. A Roadmap for Controlled Production of Topological Insulator Nanostructures and Thin Films. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2015; 11:3290-3305. [PMID: 25727694 DOI: 10.1002/smll.201403426] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 01/14/2015] [Indexed: 06/04/2023]
Abstract
The group V-VI chalcogenide semiconductors (Bi2 Se3 , Bi2 Te3 , and Sb2 Te3 ) have long been known as thermoelectric materials. Recently, they have been once more generating interest because Bi2 Se3 , Bi2 Te3 and Sb2 Te3 have been crowned as 3D topological insulators (TIs), which have insulating bulk gaps and metallic Dirac surface states. One big challenge in the study of TIs is the lack of high-quality materials with few defects and insulating bulk states. To manifest the topological surface states, it is critical to suppress the contribution from the bulk carriers. Controlled production of TI nanostructures that have a large surface-to-volume ratio is an efficient way to reduce the bulk conductance and to significantly enhance the topological surface conduction. In this review article, the recent progress on the preparation of TI nanostructures is highlighted. Basic production methods for TI nanostructures are introduced in detail. Furthermore, several specific production approaches to reduce the residual bulk carriers from defects are summarized. Finally, the progress and the prospects of the production of TI-based heterostructures, which hold promise in both fundamental study and novel applications are discussed.
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Affiliation(s)
- Yunfan Guo
- Center for Nanochemistry, Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P.R. China
| | - Zhongfan Liu
- Center for Nanochemistry, Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P.R. China
| | - Hailin Peng
- Center for Nanochemistry, Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P.R. China
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28
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Tian H, Wang S, Hu J, Wang J. The chirality dependent spin filter design in the graphene-like junction. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:125005. [PMID: 25694439 DOI: 10.1088/0953-8984/27/12/125005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We investigate the chirality-dependent spin transport in a graphene-like topological insulator (TI) TI/n junction, where a perpendicular magnetic field or an off-resonant circularly- polarized light field is applied to the normal (n) region. It is found that the coupling between the helical edge states of the TI and chiral edge states from the magnetic/light field results in a perfect spin filtering effect and only one spin species can tunnel through the junction interface. The origin is ascribed to the chirality-conservation requirement, since the two spin species have the opposite chiralities in the TI region and in the n region both of them have the same chiralities. For a TI/n superlattice structure, the spin filtering effect is enhanced and even survives in a fairly strong disorder environment.
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Affiliation(s)
- Hongyu Tian
- Department of Physics, Yancheng Institute of Technology, Jiangsu 224051, People's Republic of China
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29
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Ludwig T, Guo L, McCrary P, Zhang Z, Gordon H, Quan H, Stanton M, Frazier RM, Rogers RD, Wang HT, Turner CH. Mechanism of bismuth telluride exfoliation in an ionic liquid solvent. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:3644-3652. [PMID: 25760309 DOI: 10.1021/acs.langmuir.5b00239] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Bismuth telluride (Bi2Te3) is a well-known thermoelectric material that has a layered crystal structure. Exfoliating Bi2Te3 to produce two-dimensional (2D) nanosheets is extremely important because the exfoliated nanosheets possess unique properties, which can potentially revolutionize several material technologies such as thermoelectrics, heterogeneous catalysts, and infrared detectors. In this work, ionic liquid (IL) 1-butyl-3-methylimidazolium chloride ([C4mim]Cl) is used to exfoliate Bi2Te3 nanoplatelets. In both experiments and in molecular dynamics (MD) simulations, the Bi2Te3 nanoplatelets yield a stable dispersion of 2D nanosheets in the IL solvent, and our MD simulations provide molecular-level insight into the kinetics and thermodynamics of the exfoliation process. An analysis of the dynamics of Bi2Te3 during exfoliation indicates that the relative translation (sliding apart) of adjacent layers caused by IL-induced forces plays an important role in the process. Moreover, an evaluation of the MD trajectories and electrostatic interactions indicates that the [C4mim](+) cation is primarily responsible for initiating Bi2Te3 layer sliding and separation, while the Cl(-) anion is less active. Overall, our combined experimental and computational investigation highlights the effectiveness of IL-assisted exfoliation, and the underlying molecular-level insights should accelerate the development of future exfoliation techniques for producing 2D chalcogenide materials.
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Affiliation(s)
| | | | | | | | - Haley Gordon
- ⊥Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
- #St. Mary's College, Notre Dame, Indiana 46556, United States
| | | | - Michael Stanton
- ∇Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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30
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31
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Yuan H, Wang H, Cui Y. Two-dimensional layered chalcogenides: from rational synthesis to property control via orbital occupation and electron filling. Acc Chem Res 2015; 48:81-90. [PMID: 25553585 DOI: 10.1021/ar5003297] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Electron occupation of orbitals in two-dimensional (2D) layered materials controls the magnitude and anisotropy of the interatomic electron transfer and exerts a key influence on the chemical bonding modes of 2D layered lattices. Therefore, their orbital occupations are believed to be responsible for massive variations of the physical and chemical properties from electrocatalysis and energy storage, to charge density waves, superconductivity, spin-orbit coupling, and valleytronics. Especially in nanoscale structures such as nanoribbons, nanoplates, and nanoflakes, 2D layered materials provide opportunities to exploit new quantum phenomena. In this Account, we report our recent progress in the rational design and chemical, electrochemical, and electrical modulations of the physical and chemical properties of layered nanomaterials via modification of the electron occupation in their electronic structures. Here, we start with the growth and fabrication of a group of layered chalcogenides with varied orbital occupation (from 4d/5d electron configuration to 5p/6p electron configuration). The growth techniques include bottom-up methods, such as vapor-liquid-solid growth and vapor-solid growth, and top-down methods, such as mechanical exfoliation with tape and AFM tip scanning. Next, we demonstrate the experimental strategies for the tuning of the chemical potential (orbital occupation tuned with electron filling) and the resulting modulation of the electronic states of layered materials, such as electric-double-layer gating, electrochemical intercalation, and chemical intercalation with molecule and zerovalence metal species. Since the properties of layered chalcogenides are normally dominated by the specific band structure around which the chemical potential is sitting, their desired electronic states and properties can be modulated in a large range, showing unique phenomena including quantum electronic transport and extraordinary optical transmittance. As the most important part of this Account, we further demonstrate some representative examples for the tuning of catalytic, optical, electronic, and spintronic properties of 2D layered chalcogenides, where one can see not only edge-state induced enhancement of catalysis, quantum Aharonov-Bohm interference of the topological surface states, intercalation modulated extraordinary transmittance, and surface plasmonics but also external gating induced superconductivity and spin-coupled valley photocurrent. Since our findings reflect the critical influences of the electron filling of orbital occupation to the properties in 2D layered chalcogenides, we thus last highlight the importance and the prospective of orbital occupation in 2D layered materials for further exploring potential functionalized applications.
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Affiliation(s)
- Hongtao Yuan
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, United States
- Stanford Institute for Materials and Energy
Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Haotian Wang
- Department of Applied Physics, Stanford University, Stanford, California 94305, United States
| | - Yi Cui
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, United States
- Stanford Institute for Materials and Energy
Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
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32
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Huang YK, Cain JD, Peng L, Hao S, Chasapis T, Kanatzidis MG, Wolverton C, Grayson M, Dravid VP. Evaporative thinning: a facile synthesis method for high quality ultrathin layers of 2D crystals. ACS NANO 2014; 8:10851-7. [PMID: 25233478 DOI: 10.1021/nn504664p] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The palette of two-dimensional materials has expanded beyond graphene in recent years to include the chalcogenides among other systems. However, there is a considerable paucity of methods for controlled synthesis of mono- and/or few-layer two-dimensional materials with desirable quality, reproducibility, and generality. Here we show a facile top-down synthesis approach for ultrathin layers of 2D materials down to monolayer. Our method is based on controlled evaporative thinning of initially large sheets, as deposited by vapor mass-transport. Rather than optimizing conditions for monolayer deposition, our approach makes use of selective evaporation of thick sheets to control the eventual thickness, down to a monolayer, a process which appears to be self-stopping. As a result, 2D sheets with high yield, high reproducibility, and excellent quality can be generated with large (>10 μm) and thin (∼ 1-2 nm) dimensions. Evaporative thinning promises to greatly reduce the difficulty involved in isolating large, mono- and few-layers of 2D materials for subsequent studies.
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Affiliation(s)
- Yi-Kai Huang
- Department of Materials Science and Engineering, ‡Department of Electrical Engineering and Computer Science, §Department of Applied Physics, and ∥Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States
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33
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Kambe T, Sakamoto R, Kusamoto T, Pal T, Fukui N, Hoshiko K, Shimojima T, Wang Z, Hirahara T, Ishizaka K, Hasegawa S, Liu F, Nishihara H. Redox Control and High Conductivity of Nickel Bis(dithiolene) Complex π-Nanosheet: A Potential Organic Two-Dimensional Topological Insulator. J Am Chem Soc 2014; 136:14357-60. [DOI: 10.1021/ja507619d] [Citation(s) in RCA: 330] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Tetsuya Kambe
- Department
of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Ryota Sakamoto
- Department
of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Tetsuro Kusamoto
- Department
of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Tigmansu Pal
- Department
of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Naoya Fukui
- Department
of Physics, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Ken Hoshiko
- Department
of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Takahiro Shimojima
- Quantum-Phase
Electronics Center (QPEC) and Department of Applied Physics, Graduate
School of Engineering, The University of Tokyo, 7-3-1, Hongo,
Bunkyo-ku, Tokyo 113-8656, Japan
| | - Zhengfei Wang
- Department
of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, United States
| | - Toru Hirahara
- Department
of Physics, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kyoko Ishizaka
- Quantum-Phase
Electronics Center (QPEC) and Department of Applied Physics, Graduate
School of Engineering, The University of Tokyo, 7-3-1, Hongo,
Bunkyo-ku, Tokyo 113-8656, Japan
| | - Shuji Hasegawa
- Department
of Physics, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Feng Liu
- Department
of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, United States
| | - Hiroshi Nishihara
- Department
of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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34
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Zhao S, Li Z, Yang J. Obtaining two-dimensional electron gas in free space without resorting to electron doping: an electride based design. J Am Chem Soc 2014; 136:13313-8. [PMID: 25188520 DOI: 10.1021/ja5065125] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Nearly free electron (NFE) states are widely existed on atomically smooth surfaces in two-dimensional materials. Since they are mainly distributed in free space, these states can in principle provide ideal electron transport channels without nuclear scattering. Unfortunately, NFE states are typically unoccupied, and electron doping is required to shift them toward the Fermi level and, thus, to be involved in electron transport. Instead of occupying these NFE states, it is more desirable to have intrinsic nucleus-free two-dimensional electron gas in free space (2DEG-FS) at the Fermi level without relying on doping. Inspired by a recently identified electride material, we suggest that Ca2N monolayer should possess such a 2DEG-FS state, which is then confirmed by our first-principles calculations. Phonon dispersion in Ca2N monolayer shows no imagery frequency indicating that the monolayer structure is stable. A mechanical analysis demonstrates that Ca2N bulk exfoliation is feasible to produce a freestanding monolayer. However, in real applications, the strong chemical activity of 2DEG-FS may become a practical issue. It is found that some ambient molecules can dissociatively adsorb on the Ca2N monolayer, accompanying with a significant charge transfer from the 2DEG-FS state to adsorbates. To protect the 2DEG-FS state from molecule adsorption, we predict that graphane can be used as an effective encapsulating material. A well-encapsulated intrinsic 2DEG-FS state is expected to play an important role in low-dimensional electronics by realizing nuclear scattering free transport.
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Affiliation(s)
- Songtao Zhao
- Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China , Hefei, Anhui 230026, China
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35
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Sun Y, Gao S, Xie Y. Atomically-thick two-dimensional crystals: electronic structure regulation and energy device construction. Chem Soc Rev 2014; 43:530-46. [PMID: 24122032 DOI: 10.1039/c3cs60231a] [Citation(s) in RCA: 160] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Atomically-thick two-dimensional crystals can provide promising opportunities to satisfy people's requirement of next-generation flexible and transparent nanodevices. However, the characterization of these low-dimensional structures and the understanding of their clear structure-property relationship encounter many great difficulties, owing to the lack of long-range order in the third dimensionality. In this review, we survey the recent progress in fine structure characterization by X-ray absorption fine structure spectroscopy and also overview electronic structure modulation by density-functional calculations in the ultrathin two-dimensional crystals. In addition, we highlight their structure-property relationship, transparent and flexible device construction as well as wide applications in photoelectrochemical water splitting, photodetectors, thermoelectric conversion, touchless moisture sensing, supercapacitors and lithium ion batteries. Finally, we outline the major challenges and opportunities that face the atomically-thick two-dimensional crystals. It is anticipated that the present review will deepen people's understanding of this field and hence contribute to guide the future design of high-efficiency energy-related devices.
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Affiliation(s)
- Yongfu Sun
- Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science & Technology of China, Hefei, 230026, P.R. China.
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36
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Surrounding sensitive electronic properties of Bi₂Te₃ nanoplates-potential sensing applications of topological insulators. Sci Rep 2014; 4:4639. [PMID: 24717774 PMCID: PMC3982166 DOI: 10.1038/srep04639] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Accepted: 03/20/2014] [Indexed: 11/08/2022] Open
Abstract
Significant efforts have been paid to exploring the fundamental properties of topological insulators (TIs) in recent years. However, the investigation of TIs as functional materials for practical device applications is still quite limited. In this work, electronic sensors based on Bi2Te3 nanoplates were fabricated and the sensing performance was investigated. On exposure to different surrounding environments, significant changes in the conducting properties were observed by direct electrical measurements. These results suggest that nanostructured TIs hold great potential for sensing applications.
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37
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Bansal N, Cho MR, Brahlek M, Koirala N, Horibe Y, Chen J, Wu W, Park YD, Oh S. Transferring MBE-grown topological insulator films to arbitrary substrates and metal-insulator transition via Dirac gap. NANO LETTERS 2014; 14:1343-1348. [PMID: 24576215 DOI: 10.1021/nl404363b] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Mechanical exfoliation of bulk crystals has been widely used to obtain thin topological insulator (TI) flakes for device fabrication. However, such a process produces only microsized flakes that are highly irregular in shape and thickness. In this work, we developed a process to transfer the entire area of TI Bi2Se3 thin films grown epitaxially on Al2O3 and SiO2 to arbitrary substrates, maintaining their pristine morphology and crystallinity. Transport measurements show that these transferred films have lower carrier concentrations and comparable or higher mobilities than before the transfer. Furthermore, using this process we demonstrated a clear metal-insulator transition in an ultrathin Bi2Se3 film by gate-tuning its Fermi level into the hybridization gap formed at the Dirac point. The ability to transfer large area TI films to any substrate will facilitate fabrication of TI heterostructure devices, which will help explore exotic phenomena such as Majorana fermions and topological magnetoelectricity.
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Affiliation(s)
- Namrata Bansal
- Department of Electrical and Computer Engineering, Rutgers, the State University of New Jersey , Piscataway, New Jersey 08854, United States
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38
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39
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Vargas A, Basak S, Liu F, Wang B, Panaitescu E, Lin H, Markiewicz R, Bansil A, Kar S. The changing colors of a quantum-confined topological insulator. ACS NANO 2014; 8:1222-1230. [PMID: 24428365 DOI: 10.1021/nn404013d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Bismuth selenide (Bi2Se3) is a 3D topological insulator, its strong spin-orbit coupling resulting in the well-known topologically protected coexistence of gapless metallic surface states and semiconducting bulk states with a band gap, Eg ≃ 300 meV. A fundamental question of considerable importance is how the electronic properties of this material evolve under nanoscale confinement. We report on catalyst-free, high-quality single-crystalline Bi2Se3 with controlled lateral sizes and layer thicknesses that could be tailored down to a few nanometers and a few quintuple layers (QLs), respectively. Energy-resolved photoabsorption spectroscopy (1.5 eV < E(photon) < 6 eV) of these samples reveals a dramatic evolution of the photon absorption spectra as a function of size, transitioning from a featureless metal-like spectrum in the bulk (corresponding to a visually gray color), to one with a remarkably large band gap (Eg ≥ 2.5 eV) and a spectral shape that correspond to orange-red colorations in the smallest samples, similar to those seen in semiconductor nanostructures. We analyze this colorful transition using ab initio density functional theory and tight-binding calculations which corroborate our experimental findings and further suggest that while purely 2D sheets of few QL-thick Bi2Se3 do exhibit small band gaps that are consistent with previous ARPES results, the presently observed large gaps of a few electronvolts can only result from a combined effect of confinement in all three directions.
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Affiliation(s)
- Anthony Vargas
- Department of Physics, Northeastern University , Boston Massachusetts, United States
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40
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Chatterjee A, Guin SN, Biswas K. Ultrathin septuple layered PbBi2Se4 nanosheets. Phys Chem Chem Phys 2014; 16:14635-9. [DOI: 10.1039/c4cp01885k] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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41
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Lei S, Ge L, Liu Z, Najmaei S, Shi G, You G, Lou J, Vajtai R, Ajayan PM. Synthesis and photoresponse of large GaSe atomic layers. NANO LETTERS 2013; 13:2777-81. [PMID: 23731066 DOI: 10.1021/nl4010089] [Citation(s) in RCA: 136] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We report the direct growth of large, atomically thin GaSe single crystals on insulating substrates by vapor phase mass transport. A correlation is identified between the number of layers and a Raman shift and intensity change. We found obvious contrast of the resistance of the material in the dark and when illuminated with visible light. In the photoconductivity measurement we observed a low dark current. The on-off ratio measured with a 405 nm at 0.5 mW/mm(2) light source is in the order of 10(3); the photoresponsivity is 17 mA/W, and the quantum efficiency is 5.2%, suggesting possibility for photodetector and sensor applications. The photocurrent spectrum of few-layer GaSe shows an intense blue shift of the excitation edge and expanded band gap compared with bulk material.
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Affiliation(s)
- Sidong Lei
- Department of Mechanical Engineering and Materials Science, Rice University, Houston, Texas 77005, USA
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42
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Sabater C, Gosálbez-Martínez D, Fernández-Rossier J, Rodrigo JG, Untiedt C, Palacios JJ. Topologically protected quantum transport in locally exfoliated bismuth at room temperature. PHYSICAL REVIEW LETTERS 2013; 110:176802. [PMID: 23679755 DOI: 10.1103/physrevlett.110.176802] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 12/12/2012] [Indexed: 06/02/2023]
Abstract
We report electrical conductance measurements of Bi nanocontacts created by repeated tip-surface indentation using a scanning tunneling microscope at temperatures of 4 and 300 K. As a function of the elongation of the nanocontact, we measure robust, tens of nanometers long plateaus of conductance G0 = 2e2/h at room temperature. This observation can be accounted for by the mechanical exfoliation of a Bi(111) bilayer, a predicted quantum spin Hall (QSH) insulator, in the retracing process following a tip-surface contact. The formation of the bilayer is further supported by the additional observation of conductance steps below G0 before breakup at both temperatures. Our finding provides the first experimental evidence of the possibility of mechanical exfoliation of Bi bilayers, the existence of the QSH phase in a two-dimensional crystal, and, most importantly, the observation of the QSH phase at room temperature.
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Affiliation(s)
- C Sabater
- Departamento de Física Aplicada, Universidad de Alicante, San Vicente del Raspeig, Alicante 03690, Spain
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43
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Zhou J, Chen G, Nie B, Zuo J, Song J, Luo L, Yang Q. Growth of multi-step shaped CdTe nanowires and a distinct photoelectric response in a single nanowire. CrystEngComm 2013. [DOI: 10.1039/c3ce40650d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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44
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Fang L, Jia Y, Miller DJ, Latimer ML, Xiao ZL, Welp U, Crabtree GW, Kwok WK. Catalyst-free growth of millimeter-long topological insulator Bi₂Se₃ nanoribbons and the observation of the π-Berry phase. NANO LETTERS 2012; 12:6164-9. [PMID: 23126261 DOI: 10.1021/nl302989v] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We report the growth of single-crystalline Bi(2)Se(3) nanoribbons with lengths up to several millimeters via a catalyst-free physical vapor deposition method. Scanning transmission electron microscopy analysis reveals that the nanoribbons grow along the (112̅0) direction. We obtain a detailed characterization of the electronic structure of the Bi(2)Se(3) nanoribbons from measurements of Shubnikov-de Haas (SdH) quantum oscillations. Angular dependent magneto-transport measurements reveal a dominant two-dimensional contribution originating from surface states. The catalyst-free synthesis yields high-purity nanocrystals enabling the observation of a large number of SdH oscillation periods and allowing for an accurate determination of the π-Berry phase, one of the key features of Dirac fermions in topological insulators. The long-length nanoribbons open the possibility for fabricating multiple nanoelectronic devices on a single nanoribbon.
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Affiliation(s)
- L Fang
- Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60565, United States.
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45
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Sun Y, Cheng H, Gao S, Liu Q, Sun Z, Xiao C, Wu C, Wei S, Xie Y. Atomically Thick Bismuth Selenide Freestanding Single Layers Achieving Enhanced Thermoelectric Energy Harvesting. J Am Chem Soc 2012; 134:20294-7. [DOI: 10.1021/ja3102049] [Citation(s) in RCA: 249] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yongfu Sun
- Hefei National Laboratory
for
Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, P. R.
China
| | - Hao Cheng
- National Synchrotron
Radiation
Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, P. R. China
| | - Shan Gao
- Hefei National Laboratory
for
Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, P. R.
China
| | - Qinghua Liu
- National Synchrotron
Radiation
Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, P. R. China
| | - Zhihu Sun
- National Synchrotron
Radiation
Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, P. R. China
| | - Chong Xiao
- Hefei National Laboratory
for
Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, P. R.
China
| | - Changzheng Wu
- Hefei National Laboratory
for
Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, P. R.
China
| | - Shiqiang Wei
- National Synchrotron
Radiation
Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, P. R. China
| | - Yi Xie
- Hefei National Laboratory
for
Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, P. R.
China
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46
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Braga D, Gutiérrez Lezama I, Berger H, Morpurgo AF. Quantitative determination of the band gap of WS2 with ambipolar ionic liquid-gated transistors. NANO LETTERS 2012; 12:5218-23. [PMID: 22989251 DOI: 10.1021/nl302389d] [Citation(s) in RCA: 206] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We realized ambipolar field-effect transistors by coupling exfoliated thin flakes of tungsten disulfide (WS(2)) with an ionic liquid dielectric. The devices show ideal electrical characteristics, including very steep subthreshold slopes for both electrons and holes and extremely low OFF-state currents. Thanks to these ideal characteristics, we determine with high precision the size of the band gap of WS(2) directly from the gate-voltage dependence of the source-drain current. Our results demonstrate how a careful use of ionic liquid dielectrics offers a powerful strategy to study quantitatively the electronic properties of nanoscale materials.
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Affiliation(s)
- Daniele Braga
- DPMC and GAP, Université de Genéve, 24 quai Ernest Ansermet, CH-1211 Geneva, Switzerland.
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47
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Yan Y, Liao ZM, Yu F, Wu HC, Jing G, Yang ZC, Zhao Q, Yu D. Synthesis and field emission properties of topological insulator Bi₂Se₃ nanoflake arrays. NANOTECHNOLOGY 2012; 23:305704. [PMID: 22781636 DOI: 10.1088/0957-4484/23/30/305704] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
High quality Bi(2)Se(3) nanoflake arrays with a large area and high-yield production have been fabricated by chemical vapor deposition. As the essential candidate for a topological insulator, the unique surface electronic states are considered to play a crucial role distinct from the bulk. Our experimental results show that environmental doping significantly affects the field emission properties of the synthesized Bi(2)Se(3) nanoflake arrays. X-ray photoelectron spectroscopy characterizations indicate that the rapid surface oxidation may prohibit the detection of the topological surface state and results in a low field emission current. This work provides another insight to investigate the surface state of topological insulator materials.
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Affiliation(s)
- Yuan Yan
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, People's Republic of China
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48
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Cao H, Tian J, Miotkowski I, Shen T, Hu J, Qiao S, Chen YP. Quantized Hall effect and Shubnikov-de Haas oscillations in highly doped Bi2Se3: evidence for layered transport of bulk carriers. PHYSICAL REVIEW LETTERS 2012; 108:216803. [PMID: 23003290 DOI: 10.1103/physrevlett.108.216803] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2011] [Indexed: 06/01/2023]
Abstract
Bi2Se3 is an important semiconductor thermoelectric material and a prototype topological insulator. Here we report observation of Shubnikov-de Hass oscillations accompanied by quantized Hall resistances (R(xy)) in highly doped n-type Bi2Se3 with bulk carrier concentrations of few 10(19) cm(-3). Measurements under tilted magnetic fields show that the magnetotransport is 2D-like, where only the c-axis component of the magnetic field controls the Landau level formation. The quantized step size in 1/R(xy) is found to scale with the sample thickness, and average ~e(2)/h per quintuple layer. We show that the observed magnetotransport features do not come from the sample surface, but arise from the bulk of the sample acting as many parallel 2D electron systems to give a multilayered quantum Hall effect. In addition to revealing a new electronic property of Bi2Se3, our finding also has important implications for electronic transport studies of topological insulator materials.
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Affiliation(s)
- Helin Cao
- Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA
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Barboza APM, Chacham H, Oliveira CK, Fernandes TFD, Ferreira EHM, Archanjo BS, Batista RJC, de Oliveira AB, Neves BRA. Dynamic negative compressibility of few-layer graphene, h-BN, and MoS2. NANO LETTERS 2012; 12:2313-2317. [PMID: 22468807 DOI: 10.1021/nl300183e] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We report a novel mechanical response of few-layer graphene, h-BN, and MoS(2) to the simultaneous compression and shear by an atomic force microscope (AFM) tip. The response is characterized by the vertical expansion of these two-dimensional (2D) layered materials upon compression. Such effect is proportional to the applied load, leading to vertical strain values (opposite to the applied force) of up to 150%. The effect is null in the absence of shear, increases with tip velocity, and is anisotropic. It also has similar magnitudes in these solid lubricant materials (few-layer graphene, h-BN, and MoS(2)), but it is absent in single-layer graphene and in few-layer mica and Bi(2)Se(3). We propose a physical mechanism for the effect where the combined compressive and shear stresses from the tip induce dynamical wrinkling on the upper material layers, leading to the observed flake thickening. The new effect (and, therefore, the proposed wrinkling) is reversible in the three materials where it is observed.
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Affiliation(s)
- Ana Paula M Barboza
- Departamento de Física, ICEx, Universidade Federal de Minas Gerais (UFMG), CP 702, 30123-970 Belo Horizonte, Brazil
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50
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Li H, Lu G, Yin Z, He Q, Li H, Zhang Q, Zhang H. Optical identification of single- and few-layer MoS₂ sheets. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2012; 8:682-6. [PMID: 22223545 DOI: 10.1002/smll.201101958] [Citation(s) in RCA: 135] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Indexed: 05/25/2023]
Abstract
A simple approach is developed to identify the layer number of 2D MoS₂ sheets. By using an optical imaging method combined with image analysis software, a high-contrast image of the MoS₂ sheets can be extracted from the red (R) channel of the color optical microscopy image. The value of the intensity difference in the grayscale image of the R channel between MoS₂ sheets (1-3 layers) and the SiO₂ substrate can be used to identify the layer number of the sheet.
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Affiliation(s)
- Hai Li
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
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