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Tan CM, Fukui N, Takada K, Maeda H, Selezneva E, Bourgès C, Masunaga H, Sasaki S, Tsukagoshi K, Mori T, Sirringhaus H, Nishihara H. Lateral Heterometal Junction Rectifier Fabricated by Sequential Transmetallation of Coordination Nanosheet. Angew Chem Int Ed Engl 2024; 63:e202318181. [PMID: 38179847 DOI: 10.1002/anie.202318181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 12/22/2023] [Accepted: 01/03/2024] [Indexed: 01/06/2024]
Abstract
Heterostructures of two-dimensional materials realise novel and enhanced physical phenomena, making them attractive research targets. Compared to inorganic materials, coordination nanosheets have virtually infinite combinations, leading to tunability of physical properties and are promising candidates for heterostructure fabrication. Although stacking of coordination materials into vertical heterostructures is widely reported, reports of lateral coordination material heterostructures are few. Here we show the successful fabrication of a seamless lateral heterojunction showing diode behaviour, by sequential and spatially limited immersion of a new metalladithiolene coordination nanosheet, Zn3 BHT, into aqueous Cu(II) and Fe(II) solutions. Upon immersion, the Zn centres in insulating Zn3 BHT are replaced by Cu or Fe ions, resulting in conductivity. The transmetallation is spatially confined, occurring only within the immersed area. We anticipate that our results will be a starting point towards exploring transmetallation of various two-dimensional materials to produce lateral heterojunctions, by providing a new and facile synthetic route.
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Affiliation(s)
- Choon Meng Tan
- Research Institute for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278 8510, Japan
| | - Naoya Fukui
- Research Institute for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278 8510, Japan
| | - Kenji Takada
- Research Institute for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278 8510, Japan
| | - Hiroaki Maeda
- Research Institute for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278 8510, Japan
| | - Ekaterina Selezneva
- Research Institute for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278 8510, Japan
- WPI International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, 305-0044, Japan
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK
| | - Cédric Bourgès
- International Center for Young Scientists (ICYS), National Institute for Materials Science (NIMS), Namiki, Tsukuba, 305-0044, Japan
| | - Hiroyasu Masunaga
- Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, (Japan)
| | - Sono Sasaki
- Faculty of Fiber Science and Engineering, Kyoto Institute of Technology, 1 Matsugasaki Hashikami-cho, Sakyo-ku, Kyoto 606-8585, Japan
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Kazuhito Tsukagoshi
- WPI International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, 305-0044, Japan
| | - Takao Mori
- WPI International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, 305-0044, Japan
| | - Henning Sirringhaus
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK
| | - Hiroshi Nishihara
- Research Institute for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278 8510, Japan
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2
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Mahdaoui D, Hirata C, Nagaoka K, Miyazawa K, Fujii K, Ando T, Abderrabba M, Ito O, Yagyu S, Liu Y, Nakajima Y, Tsukagoshi K, Wakahara T. Ambipolar to Unipolar Conversion in C 70/Ferrocene Nanosheet Field-Effect Transistors. Nanomaterials (Basel) 2023; 13:2469. [PMID: 37686977 PMCID: PMC10490395 DOI: 10.3390/nano13172469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/28/2023] [Accepted: 08/29/2023] [Indexed: 09/10/2023]
Abstract
Organic cocrystals, which are assembled by noncovalent intermolecular interactions, have garnered intense interest due to their remarkable chemicophysical properties and practical applications. One notable feature, namely, the charge transfer (CT) interactions within the cocrystals, not only facilitates the formation of an ordered supramolecular network but also endows them with desirable semiconductor characteristics. Here, we present the intriguing ambipolar CT properties exhibited by nanosheets composed of single cocrystals of C70/ferrocene (C70/Fc). When heated to 150 °C, the initially ambipolar monoclinic C70/Fc nanosheet-based field-effect transistors (FETs) were transformed into n-type face-centered cubic (fcc) C70 nanosheet-based FETs owing to the elimination of Fc. This thermally induced alteration in the crystal structure was accompanied by an irreversible switching of the semiconducting behavior of the device; thus, the device transitions from ambipolar to unipolar. Importantly, the C70/Fc nanosheet-based FETs were also found to be much more thermally stable than the previously reported C60/Fc nanosheet-based FETs. Furthermore, we conducted visible/near-infrared diffuse reflectance and photoemission yield spectroscopies to investigate the crucial role played by Fc in modulating the CT characteristics. This study provides valuable insights into the overall functionality of these nanosheet structures.
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Affiliation(s)
- Dorra Mahdaoui
- Electronic Functional Macromolecules Group, Research Center for Macromolecules and Biomaterials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Ibaraki, Japan; (C.H.); (K.N.); (K.F.); (T.A.); (O.I.)
- Laboratory of Materials, Molecules and Applications, Preparatory Institute for Scientific and Technical Studies, University of Carthage, B.P. 51, La Marsa 2075, Tunisia;
| | - Chika Hirata
- Electronic Functional Macromolecules Group, Research Center for Macromolecules and Biomaterials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Ibaraki, Japan; (C.H.); (K.N.); (K.F.); (T.A.); (O.I.)
| | - Kahori Nagaoka
- Electronic Functional Macromolecules Group, Research Center for Macromolecules and Biomaterials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Ibaraki, Japan; (C.H.); (K.N.); (K.F.); (T.A.); (O.I.)
| | - Kun’ichi Miyazawa
- Department of Industrial Chemistry, Faculty of Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan;
| | - Kazuko Fujii
- Electronic Functional Macromolecules Group, Research Center for Macromolecules and Biomaterials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Ibaraki, Japan; (C.H.); (K.N.); (K.F.); (T.A.); (O.I.)
| | - Toshihiro Ando
- Electronic Functional Macromolecules Group, Research Center for Macromolecules and Biomaterials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Ibaraki, Japan; (C.H.); (K.N.); (K.F.); (T.A.); (O.I.)
| | - Manef Abderrabba
- Laboratory of Materials, Molecules and Applications, Preparatory Institute for Scientific and Technical Studies, University of Carthage, B.P. 51, La Marsa 2075, Tunisia;
| | - Osamu Ito
- Electronic Functional Macromolecules Group, Research Center for Macromolecules and Biomaterials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Ibaraki, Japan; (C.H.); (K.N.); (K.F.); (T.A.); (O.I.)
| | - Shinjiro Yagyu
- Nano Electronics Device Materials Group, Research Center for Electronic and Optical Materials, 1-1 Namiki, Tsukuba 305-0044, Ibaraki, Japan;
| | - Yubin Liu
- RIKEN KEIKI Co., Ltd., 2-7-6, Azusawa, Itabashi-ku, Tokyo 174-8744, Japan; (Y.L.); (Y.N.)
| | - Yoshiyuki Nakajima
- RIKEN KEIKI Co., Ltd., 2-7-6, Azusawa, Itabashi-ku, Tokyo 174-8744, Japan; (Y.L.); (Y.N.)
| | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Ibaraki, Japan;
| | - Takatsugu Wakahara
- Electronic Functional Macromolecules Group, Research Center for Macromolecules and Biomaterials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Ibaraki, Japan; (C.H.); (K.N.); (K.F.); (T.A.); (O.I.)
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3
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Homma K, Kaneko S, Tsukagoshi K, Nishino T. Intermolecular and Electrode-Molecule Bonding in a Single Dimer Junction of Naphthalenethiol as Revealed by Surface-Enhanced Raman Scattering Combined with Transport Measurements. J Am Chem Soc 2023. [PMID: 37437895 PMCID: PMC10375526 DOI: 10.1021/jacs.3c02050] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/14/2023]
Abstract
Electron transport through noncovalent interaction is of fundamental and practical importance in nanomaterials and nanodevices. Recent single-molecule studies employing single-molecule junctions have revealed unique electron transport properties through noncovalent interactions, especially those through a π-π interaction. However, the relationship between the junction structure and electron transport remains elusive due to the insufficient knowledge of geometric structures. In this article, we employ surface-enhanced Raman scattering (SERS) synchronized with current-voltage (I-V) measurements to characterize the junction structure, together with the transport properties, of a single dimer and monomer junction of naphthalenethiol, the former of which was formed by the intermolecular π-π interaction. The correlation analysis of the vibrational energy and electrical conductance enables identifying the intermolecular and molecule-electrode interactions in these molecular junctions and, consequently, addressing the transport properties exclusively associated with the π-π interaction. In addition, the analysis achieved discrimination of the interaction between the NT molecule and the Au electrode of the junction, i.e., Au-π interactions through-π coupling and though-space coupling. The power density spectra support the noncovalent character at the interfaces in the molecular junctions. These results demonstrate that the simultaneous SERS and I-V technique provides a unique means for the structural and electrical investigation of noncovalent interactions.
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Affiliation(s)
- Kanji Homma
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Satoshi Kaneko
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Tomoaki Nishino
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
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4
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Nurdiwijayanto L, Hayashi K, Sakai N, Ebina Y, Tang DM, Ueda S, Osada M, Tsukagoshi K, Sasaki T, Taniguchi T. Thermal and Chemical Phase Engineering of Two-Dimensional Ruthenate. ACS Nano 2023. [PMID: 37366239 DOI: 10.1021/acsnano.3c01017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
Monolayer ruthenate nanosheets obtained by exfoliating layered ruthenium oxide exhibit excellent electrical conductivity, redox activity, and catalytic activity, which render them suitable for advanced electronic and energy devices. However, to fully exploit the benefits, we require further structural insights into a complex polymorphic nature and diversity in relevant electronic states of two-dimensional (2D) ruthenate systems. In this study, the 2D structures, stability, and electronic states of 2D ruthenate are investigated on the basis of thermal and chemical phase engineering approaches. We reveal that contrary to a previous report, exfoliation of an oblique 1T phase precursor leads to nanosheets having an identical phase without exfoliation-induced phase transition to a 1H phase. The oblique 1T phase in the nanosheets is found to be metastable and, thus, transforms successively to a rectangular 1T phase upon heating. A phase-controllable synthesis via Co doping affords nanosheets with metastable rectangular and thermally stable hexagonal 1T phases at a Co content of 5-10 and 20 at%, respectively. The 1T phases show metallic electronic states, where the d-d optical transitions between the Ru 4d (t2g) orbital depend on the symmetry of the Ru framework. The Co doping in ruthenate nanosheets unexpectedly suppresses the redox and catalytic activities under acidic conditions. In contrast, the Co2+/3+ redox pair is activated and produces conductive nanosheets with high electrochemical capacitance in an alkaline condition.
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Affiliation(s)
- Leanddas Nurdiwijayanto
- Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Kensuke Hayashi
- Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Nobuyuki Sakai
- Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Yasuo Ebina
- Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Dai-Ming Tang
- Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Shigenori Ueda
- Research Center for Functional Materials, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Minoru Osada
- Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
- Institute of Materials and Systems for Sustainability, Nagoya University, Furocho, Chikusa-ku, Nagoya 464-8603, Japan
| | - Kazuhito Tsukagoshi
- Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Takayoshi Sasaki
- Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Takaaki Taniguchi
- Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
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5
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Wei CC, Wu TH, Huang JW, Young BL, Jian WB, Lin YL, Chen JT, Hsu CS, Ma YR, Tsukagoshi K. Nanoparticulate Films of WO3 and MoO3 Composites for Enhancing UV Light Electrochromic Transmittance Variation and Energy Storage Applications. Electrochim Acta 2023. [DOI: 10.1016/j.electacta.2023.141897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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6
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Lin CY, Lee MP, Chang YM, Tseng YT, Yang FS, Li M, Chen JY, Chen CF, Tsai MY, Lin YC, Ueno K, Yamamoto M, Lo ST, Lien CH, Chiu PW, Tsukagoshi K, Wu WW, Lin YF. Diffused Beam Energy to Dope van der Waals Electronics and Boost Their Contact Barrier Lowering. ACS Appl Mater Interfaces 2022; 14:41156-41164. [PMID: 36037311 DOI: 10.1021/acsami.2c07679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Contact engineering of two-dimensional semiconductors is a central issue for performance improvement of micro-/nanodevices based on these materials. Unfortunately, the various methods proposed to improve the Schottky barrier height normally require the use of high temperatures, chemical dopants, or complex processes. This work demonstrates that diffused electron beam energy (DEBE) treatment can simultaneously reduce the Schottky barrier height and enable the direct writing of electrical circuitry on van der Waals semiconductors. The electron beam energy projected into the region outside the electrode diffuses into the main channel, producing selective-area n-type doping in a layered MoTe2 (or MoS2) field-effect transistor. As a result, the Schottky barrier height at the interface between the electrode and the DEBE-treated MoTe2 channel is as low as 12 meV. Additionally, because selective-area doping is possible, DEBE can allow the formation of both n- and p-type doped channels within the same atomic plane, which enables the creation of a nonvolatile and homogeneous MoTe2 p-n rectifier with an ideality factor of 1.1 and a rectification ratio of 1.3 × 103. These results indicate that the DEBE method is a simple, efficient, mask-free, and chemical dopant-free approach to selective-area doping for the development of van der Waals electronics with excellent device performances.
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Affiliation(s)
- Che-Yi Lin
- Department of Physics, National Chung Hsing University, Taichung 40227, Taiwan
- Institute of Nanoscience, National Chung Hsing University, Taichung 40227, Taiwan
| | - Mu-Pai Lee
- Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
| | - Yuan-Ming Chang
- Department of Physics, National Chung Hsing University, Taichung 40227, Taiwan
- Institute of Nanoscience, National Chung Hsing University, Taichung 40227, Taiwan
| | - Yi-Tang Tseng
- Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
| | - Feng-Shou Yang
- Institute of Electronic Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Mengjiao Li
- Department of Physics, National Chung Hsing University, Taichung 40227, Taiwan
- Institute of Nanoscience, National Chung Hsing University, Taichung 40227, Taiwan
| | - Jiann-Yeu Chen
- Department of Material Science and Engineering and i-Center for Advanced Science and Technology (i-CAST), National Chung Hsing University, Taichung 40227, Taiwan
- Innovation and Development Center of Sustainable Agriculture, National Chung Hsing University, Taichung 40227, Taiwan
| | - Ciao-Fen Chen
- Department of Electrophysics, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
| | - Meng-Yu Tsai
- Institute of Electronic Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Yi-Chun Lin
- Instrument Center, National Chung Hsing University, Taichung 40227, Taiwan
| | - Keiji Ueno
- Department of Chemistry, Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan
| | - Mahito Yamamoto
- Department of Pure and Applied Physics, Kansai University, Osaka 564-8680, Japan
| | - Shun-Tsung Lo
- Department of Electrophysics, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
| | - Chen-Hsin Lien
- Institute of Electronic Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Po-Wen Chiu
- Institute of Electronic Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba 305-0044, Ibaraki, Japan
| | - Wen-Wei Wu
- Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
| | - Yen-Fu Lin
- Department of Physics, National Chung Hsing University, Taichung 40227, Taiwan
- Institute of Nanoscience, National Chung Hsing University, Taichung 40227, Taiwan
- Department of Material Science and Engineering and i-Center for Advanced Science and Technology (i-CAST), National Chung Hsing University, Taichung 40227, Taiwan
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7
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Wakahara T, Nagaoka K, Hirata C, Miyazawa K, Fujii K, Matsushita Y, Ito O, Takagi M, Shimazaki T, Tachikawa M, Wada Y, Yagyu S, Liu Y, Nakajima Y, Tsukagoshi K. Fullerene C 70/porphyrin hybrid nanoarchitectures: single-cocrystal nanoribbons with ambipolar charge transport properties. RSC Adv 2022; 12:19548-19553. [PMID: 35865602 PMCID: PMC9258400 DOI: 10.1039/d2ra02669d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 06/27/2022] [Indexed: 11/21/2022] Open
Abstract
In recent years, supramolecular cocrystals containing organic donors and acceptors have been explored as active components in organic field-effect transistors (FETs). Herein, we report the synthesis of novel single-cocrystal nanoribbons with ambipolar charge transport characteristics from C70 and 5,10,15,20-tetrakis(3,5-dimethoxyphenyl)porphyrin (3,5-TPP) in a 3 : 2 ratio. The C70/3,5-TPP nanoribbons exhibited a new strong absorption band in the near-infrared region, indicating the presence of charge-transfer interactions between C70 and 3,5-TPP in the cocrystals. We elucidated the mechanism of the charge-transport properties of the nanoribbons using photoemission yield spectroscopy in air and theoretical calculations. A strong interaction between porphyrins in the one-dimensional porphyrin chains formed in C70/3,5-TPP nanoribbons, which was confirmed by single-crystal X-ray diffraction, plays a crucial role in their hole transport properties. The one-dimensional porphyrin chains in the cocrystal play a very important role in the hole transport properties of C70/porphyrin nanoribbons.![]()
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Affiliation(s)
- Takatsugu Wakahara
- Research Center for Functional Materials, National Institute for Materials Science 1-1 Namiki Tsukuba Ibaraki 305-0044 Japan
| | - Kahori Nagaoka
- Research Center for Functional Materials, National Institute for Materials Science 1-1 Namiki Tsukuba Ibaraki 305-0044 Japan
| | - Chika Hirata
- Research Center for Functional Materials, National Institute for Materials Science 1-1 Namiki Tsukuba Ibaraki 305-0044 Japan
| | - Kun'ichi Miyazawa
- Department of Chemical Sciences and Technology, Graduate School of Chemical Sciences and Technology, Tokyo University of Science 6-3-1 Niijuku, Katsushika-ku Tokyo 125-8585 Japan
| | - Kazuko Fujii
- Research Center for Functional Materials, National Institute for Materials Science 1-1 Namiki Tsukuba Ibaraki 305-0044 Japan
| | - Yoshitaka Matsushita
- Research Network and Facility Services Division, National Institute for Materials Science 1-2-1 Sengen Tsukuba Ibaraki 305-0047 Japan
| | - Osamu Ito
- Research Center for Functional Materials, National Institute for Materials Science 1-1 Namiki Tsukuba Ibaraki 305-0044 Japan
| | - Makito Takagi
- Quantum Chemistry Division, Graduate School of NanoBioScience, Yokohama City University 22-2 Seto, Kanazawa-ku Yokohama Kanagawa 236-0027 Japan
| | - Tomomi Shimazaki
- Quantum Chemistry Division, Graduate School of NanoBioScience, Yokohama City University 22-2 Seto, Kanazawa-ku Yokohama Kanagawa 236-0027 Japan
| | - Masanori Tachikawa
- Quantum Chemistry Division, Graduate School of NanoBioScience, Yokohama City University 22-2 Seto, Kanazawa-ku Yokohama Kanagawa 236-0027 Japan
| | - Yoshiki Wada
- Research Center for Functional Materials, National Institute for Materials Science 1-1 Namiki Tsukuba Ibaraki 305-0044 Japan
| | - Shinjiro Yagyu
- Research Center for Functional Materials, National Institute for Materials Science 1-1 Namiki Tsukuba Ibaraki 305-0044 Japan
| | - Yubin Liu
- RIKEN KEIKI Co., Ltd 2-7-6, Azusawa Itabashi-ku Tokyo 174-8744 Japan
| | | | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science 1-1 Namiki Tsukuba Ibaraki 305-0044 Japan
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8
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Zhou J, Zhang C, Shi L, Chen X, Kim TS, Gyeon M, Chen J, Wang J, Yu L, Wang X, Kang K, Orgiu E, Samorì P, Watanabe K, Taniguchi T, Tsukagoshi K, Wang P, Shi Y, Li S. Non-invasive digital etching of van der Waals semiconductors. Nat Commun 2022; 13:1844. [PMID: 35383178 PMCID: PMC8983769 DOI: 10.1038/s41467-022-29447-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 03/14/2022] [Indexed: 11/12/2022] Open
Abstract
The capability to finely tailor material thickness with simultaneous atomic precision and non-invasivity would be useful for constructing quantum platforms and post-Moore microelectronics. However, it remains challenging to attain synchronized controls over tailoring selectivity and precision. Here we report a protocol that allows for non-invasive and atomically digital etching of van der Waals transition-metal dichalcogenides through selective alloying via low-temperature thermal diffusion and subsequent wet etching. The mechanism of selective alloying between sacrifice metal atoms and defective or pristine dichalcogenides is analyzed with high-resolution scanning transmission electron microscopy. Also, the non-invasive nature and atomic level precision of our etching technique are corroborated by consistent spectral, crystallographic, and electrical characterization measurements. The low-temperature charge mobility of as-etched MoS2 reaches up to 1200 cm2 V−1s−1, comparable to that of exfoliated pristine counterparts. The entire protocol represents a highly precise and non-invasive tailoring route for material manipulation. Here, the authors exploit a non-invasive layer-bylayer etching technique to fabricate electronic devices based on 2D transition metal dichalcogenides with controlled thickness and transport properties comparable to those of exfoliated flakes.
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Affiliation(s)
- Jian Zhou
- National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.,School of Electronic Science and Engineering, Nanjing University, Nanjing, China
| | - Chunchen Zhang
- National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.,College of Engineering and Applied Sciences and Jiangsu Key Laboratory of Artificial Functional Materials, Nanjing University, Nanjing, China
| | - Li Shi
- Department of Physics, Southeast University, Nanjing, China
| | - Xiaoqing Chen
- National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.,School of Electronic Science and Engineering, Nanjing University, Nanjing, China
| | - Tae Soo Kim
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Minseung Gyeon
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Jian Chen
- National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.,School of Electronic Science and Engineering, Nanjing University, Nanjing, China
| | - Jinlan Wang
- Department of Physics, Southeast University, Nanjing, China
| | - Linwei Yu
- National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.,School of Electronic Science and Engineering, Nanjing University, Nanjing, China
| | - Xinran Wang
- National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.,School of Electronic Science and Engineering, Nanjing University, Nanjing, China
| | - Kibum Kang
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Emanuele Orgiu
- Institut national de la recherche scientifique, Centre Énergie Matériaux Télécommunications, 1650 Blvd. Lionel-Boulet, J3X 1S2, Varennes, QC, Canada
| | - Paolo Samorì
- University of Strasbourg, CNRS, ISIS UMR 7006, 8 allée Gaspard Monge, F-67000, Strasbourg, France.
| | - Kenji Watanabe
- WPI-MANA, National Institute for Materials Science, Tsukuba, 305-0044, Ibaraki, Japan
| | - Takashi Taniguchi
- WPI-MANA, National Institute for Materials Science, Tsukuba, 305-0044, Ibaraki, Japan
| | - Kazuhito Tsukagoshi
- WPI-MANA, National Institute for Materials Science, Tsukuba, 305-0044, Ibaraki, Japan
| | - Peng Wang
- National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China. .,College of Engineering and Applied Sciences and Jiangsu Key Laboratory of Artificial Functional Materials, Nanjing University, Nanjing, China. .,Department of Physics, University of Warwick, CV4 7AL, Coventry, UK.
| | - Yi Shi
- National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China. .,School of Electronic Science and Engineering, Nanjing University, Nanjing, China.
| | - Songlin Li
- National Laboratory of Solid-State Microstructures and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China. .,School of Electronic Science and Engineering, Nanjing University, Nanjing, China.
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9
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Kobayashi S, Kaneko S, Tamaki T, Kiguchi M, Tsukagoshi K, Terao J, Nishino T. Principal Component Analysis of Surface-Enhanced Raman Scattering Spectra Revealing Isomer-Dependent Electron Transport in Spiropyran Molecular Junctions: Implications for Nanoscale Molecular Electronics. ACS Omega 2022; 7:5578-5583. [PMID: 35187372 PMCID: PMC8851897 DOI: 10.1021/acsomega.1c07105] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 01/19/2022] [Indexed: 06/14/2023]
Abstract
The characterization of single-molecule structures could provide significant insights into the operation mechanisms of functional devices. Structural transformation via isomerization has been extensively employed to implement device functionalities. Although single-molecule identification has recently been achieved using near-field spectroscopy, discrimination between isomeric forms remains challenging. Further, the structure-function relationship at the single-molecule scale remains unclear. Herein, we report the observation of the isomerization of spiropyran in a single-molecule junction (SMJ) using simultaneous surface-enhanced Raman scattering (SERS) and conductance measurements. SERS spectra were used to discriminate between isomers based on characteristic peaks. Moreover, conductance measurements, in conjunction with the principal component analysis of the SERS spectra, clearly showed the isomeric effect on the conductance of the SMJ.
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Affiliation(s)
- Shuji Kobayashi
- Department
of Chemistry, School of Science, Tokyo Institute
of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Satoshi Kaneko
- Department
of Chemistry, School of Science, Tokyo Institute
of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
- JST
PRESTO, 4-1-8 Honcho, Kawaguchi 332-0012, Japan
| | - Takashi Tamaki
- Department
of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Manabu Kiguchi
- Department
of Chemistry, School of Science, Tokyo Institute
of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Kazuhito Tsukagoshi
- International
Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Tsukuba, Ibaraki 305-0044, Japan
| | - Jun Terao
- Department
of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Tomoaki Nishino
- Department
of Chemistry, School of Science, Tokyo Institute
of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
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10
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Yasuraoka K, Kaneko S, Kobayashi S, Tsukagoshi K, Nishino T. Surface-Enhanced Raman Scattering Stimulated by Strong Metal-Molecule Interactions in a C 60 Single-Molecule Junction. ACS Appl Mater Interfaces 2021; 13:51602-51607. [PMID: 34695353 DOI: 10.1021/acsami.1c09965] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Specifying the geometric and electronic structures of a metal-molecule interface at the single-molecule level is crucial for the improvement of organic electronics. A single-molecule junction (SMJ) can be used to investigate interfaces because it can be regarded as an elementary unit of the interface structure. Although considerable efforts have been made to this end, the detection of structural changes in SMJs associated with metal-molecule interactions remains challenging. In this study, we detected the surface-enhanced Raman scattering (SERS) signal originating from the metal-molecule interaction change induced by a local structural change in a C60 SMJ. This junction has attracted wide attention owing to its unique electronic and vibronic properties. We fabricated a C60 SMJ using a lithographically fabricated Au electrode and measured the SERS spectra along with the current-voltage (I-V) response. By continuous measurement of SERS for the C60 SMJ, we obtained SERS spectra dependent on the local structural change. The analysis of the I-V response revealed that the vibration energy shift originates from the change in the local structure for different Au-C60 interactions. Based on the discrimination of the states in accordance with the Au-C60 interaction, we found that the probability of SERS for geometry with a large Au-C60 interaction was enhanced.
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Affiliation(s)
- Koji Yasuraoka
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Satoshi Kaneko
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8551, Japan
- JST PRESTO, 4-1-8 Honcho, Kawaguchi 332-0012, Japan
| | - Shuji Kobayashi
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Tsukuba, Ibaraki 305-0044, Japan
| | - Tomoaki Nishino
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8551, Japan
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11
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Wang Y, Chiang C, Chang C, Maeda H, Fukui N, Wang I, Wen C, Lu K, Huang S, Jian W, Chen C, Tsukagoshi K, Nishihara H. Two-Dimensional Bis(dithiolene)iron(II) Self-Powered UV Photodetectors with Ultrahigh Air Stability. Adv Sci (Weinh) 2021; 8:2100564. [PMID: 34306985 PMCID: PMC8292878 DOI: 10.1002/advs.202100564] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/04/2021] [Indexed: 05/26/2023]
Abstract
Organometallic two-dimensional (2D) nanosheets with tailorable components have recently fascinated the optoelectronic communities due to their solution-processable nature. However, the poor stability of organic molecules may hinder their practical application in photovoltaic devices. Instead of conventional organometallic 2D nanosheets with low weatherability, an air-stable π-conjugated 2D bis(dithiolene)iron(II) (FeBHT) coordination nanosheet (CONASH) is synthesized via bottom-up liquid/liquid interfacial polymerization using benzenehexathiol (BHT) and iron(II) ammonium sulfate [Fe(NH4)2(SO4)2] as precursors. The uncoordinated thiol groups in FeBHT are easily oxidized, but the Fe(NH4)2(SO4)2 dissociation rate is slow, which facilitates the protection of sulfur groups by iron(II) ions. The density functional theory calculates that the resultant FeBHT network gains the oxygen-repelling function for oxidation suppression. In air, the FeBHT CONASH exhibits self-powered photoresponses with short response times (<40 ms) and a spectral responsivity of 6.57 mA W-1, a specific detectivity of 3.13 × 1011 Jones and an external quantum efficiency of 2.23% under 365 nm illumination. Interestingly, the FeBHT self-powered photodetector reveals extremely high long-term air stability, maintaining over 94% of its initial photocurrent after aging for 60 days without encapsulation. These results open the prospect of using organometallic 2D materials in commercialized optoelectronic fields.
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Affiliation(s)
- Ying‐Chiao Wang
- International Center for Young Scientists (ICYS) and WPI International Center for Materials Nanoarchitectonics (WPI‐MANA)National Institute for Materials Science (NIMS)TsukubaIbaraki305‐0044Japan
| | - Chun‐Hao Chiang
- Department of Materials Science and EngineeringNational Taiwan UniversityTaipei10617Taiwan
| | - Chi‐Ming Chang
- Department of ElectrophysicsNational Chiao Tung UniversityHsinchu30010Taiwan
| | - Hiroaki Maeda
- Department of ChemistrySchool of ScienceThe University of TokyoTokyo113‐0033Japan
- Research Center for Science and TechnologyTokyo University of ScienceChiba278‐8510Japan
| | - Naoya Fukui
- Department of ChemistrySchool of ScienceThe University of TokyoTokyo113‐0033Japan
- Research Center for Science and TechnologyTokyo University of ScienceChiba278‐8510Japan
| | - I‐Ta Wang
- Department of Materials Science and EngineeringNational Taiwan UniversityTaipei10617Taiwan
| | - Cheng‐Yen Wen
- Department of Materials Science and EngineeringNational Taiwan UniversityTaipei10617Taiwan
| | - Kuan‐Cheng Lu
- Department of ElectrophysicsNational Chiao Tung UniversityHsinchu30010Taiwan
| | - Shao‐Ku Huang
- Department of Materials Science and EngineeringNational Taiwan UniversityTaipei10617Taiwan
| | - Wen‐Bin Jian
- Department of ElectrophysicsNational Chiao Tung UniversityHsinchu30010Taiwan
| | - Chun‐Wei Chen
- Department of Materials Science and EngineeringNational Taiwan UniversityTaipei10617Taiwan
- Center of Atomic Initiative for New Materials (AI‐MAT)National Taiwan UniversityTaipei10617Taiwan
| | - Kazuhito Tsukagoshi
- International Center for Young Scientists (ICYS) and WPI International Center for Materials Nanoarchitectonics (WPI‐MANA)National Institute for Materials Science (NIMS)TsukubaIbaraki305‐0044Japan
- Department of ElectrophysicsNational Chiao Tung UniversityHsinchu30010Taiwan
| | - Hiroshi Nishihara
- Department of ChemistrySchool of ScienceThe University of TokyoTokyo113‐0033Japan
- Research Center for Science and TechnologyTokyo University of ScienceChiba278‐8510Japan
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12
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Fukuzumi R, Buerkle M, Li Y, Kaneko S, Li P, Kobayashi S, Fujii S, Kiguchi M, Nakamura H, Tsukagoshi K, Nishino T. Water Splitting Induced by Visible Light at a Copper-Based Single-Molecule Junction. Small 2021; 17:e2008109. [PMID: 34089231 DOI: 10.1002/smll.202008109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 04/19/2021] [Indexed: 06/12/2023]
Abstract
Water splitting is an essential process for converting light energy into easily storable energy in the form of hydrogen. As environmentally preferable catalysts, Cu-based materials have attracted attention as water-splitting catalysts. To enhance the efficiency of water splitting, a reaction process should be developed. Single-molecule junctions (SMJs) are attractive structures for developing these reactions because the molecule electronic state is significantly modulated, and characteristic electromagnetic effects can be expected. Here, water splitting is induced at Cu-based SMJ and the produced hydrogen is characterized at a single-molecule scale by employing electron transport measurements. After visible light irradiation, the conductance states originate from Cu/hydrogen molecule/Cu junctions, while before irradiation, only Cu/water molecule/Cu junctions were observed. The vibration spectra obtained from inelastic electron tunneling spectroscopy combined with the first-principles calculations reveal that the water molecule trapped between the Cu electrodes is decomposed and that hydrogen is produced. Time-dependent and wavelength-dependent measurements show that localized-surface plasmon decomposes the water molecule in the vicinity of the junction. These findings indicate the potential ability of Cu-based materials for photocatalysis.
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Affiliation(s)
- Risa Fukuzumi
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Marius Buerkle
- CD-FMat, National Institute of Advanced Industrial Science and Technology (AIST), Central 2, Umezono 1-1-1, Tsukuba, Ibaraki, 305-8568, Japan
| | - Yu Li
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Satoshi Kaneko
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Peihui Li
- Institute of Modern Optics, Nankai University, 94 Weijin Road, Tianjin, 300350, P. R. China
| | - Shuji Kobayashi
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Shintaro Fujii
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Manabu Kiguchi
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Hisao Nakamura
- CD-FMat, National Institute of Advanced Industrial Science and Technology (AIST), Central 2, Umezono 1-1-1, Tsukuba, Ibaraki, 305-8568, Japan
| | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki, 305-0044, Japan
| | - Tomoaki Nishino
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
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13
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Li S, Hong J, Gao B, Lin Y, Lim HE, Lu X, Wu J, Liu S, Tateyama Y, Sakuma Y, Tsukagoshi K, Suenaga K, Taniguchi T. Tunable Doping of Rhenium and Vanadium into Transition Metal Dichalcogenides for Two-Dimensional Electronics. Adv Sci (Weinh) 2021; 8:e2004438. [PMID: 34105285 PMCID: PMC8188190 DOI: 10.1002/advs.202004438] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 01/24/2021] [Indexed: 05/27/2023]
Abstract
Two-dimensional (2D) transition metal dichalcogenides (TMDCs) with unique electrical properties are fascinating materials used for future electronics. However, the strong Fermi level pinning effect at the interface of TMDCs and metal electrodes always leads to high contact resistance, which seriously hinders their application in 2D electronics. One effective way to overcome this is to use metallic TMDCs or transferred metal electrodes as van der Waals (vdW) contacts. Alternatively, using highly conductive doped TMDCs will have a profound impact on the contact engineering of 2D electronics. Here, a novel chemical vapor deposition (CVD) using mixed molten salts is established for vapor-liquid-solid growth of high-quality rhenium (Re) and vanadium (V) doped TMDC monolayers with high controllability and reproducibility. A tunable semiconductor to metal transition is observed in the Re- and V-doped TMDCs. Electrical conductivity increases up to a factor of 108 in the degenerate V-doped WS2 and WSe2 . Using V-doped WSe2 as vdW contact, the on-state current and on/off ratio of WSe2 -based field-effect transistors have been substantially improved (from ≈10-8 to 10-5 A; ≈104 to 108 ), compared to metal contacts. Future studies on lateral contacts and interconnects using doped TMDCs will pave the way for 2D integrated circuits and flexible electronics.
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Affiliation(s)
- Shisheng Li
- International Center for Young Scientists (ICYS)National Institute for Materials Science (NIMS)Tsukuba305‐0044Japan
| | - Jinhua Hong
- Nanomaterials Research InstituteNational Institute of Advanced Industrial Science and TechnologyAIST Central 5Tsukuba305‐8564Japan
| | - Bo Gao
- Center for Green Research on Energy and Environmental Materials (GREEN)National Institute for Materials Science (NIMS)Tsukuba305‐0044Japan
- International Center for Materials Nanoarchitectonics (WPI‐MANA)National Institute for Materials Science (NIMS)Tsukuba305‐0044Japan
| | - Yung‐Chang Lin
- Nanomaterials Research InstituteNational Institute of Advanced Industrial Science and TechnologyAIST Central 5Tsukuba305‐8564Japan
| | - Hong En Lim
- Department of PhysicsTokyo Metropolitan UniversityHachioji192‐0397Japan
| | - Xueyi Lu
- International Center for Materials Nanoarchitectonics (WPI‐MANA)National Institute for Materials Science (NIMS)Tsukuba305‐0044Japan
| | - Jing Wu
- Institute of Materials Research and EngineeringAgency for ScienceTechnology and ResearchSingapore138634Singapore
| | - Song Liu
- Institute of Chemical Biology and Nanomedicine (ICBN)College of Chemistry and Chemical EngineeringHunan UniversityChangsha410082P. R. China
| | - Yoshitaka Tateyama
- Center for Green Research on Energy and Environmental Materials (GREEN)National Institute for Materials Science (NIMS)Tsukuba305‐0044Japan
- International Center for Materials Nanoarchitectonics (WPI‐MANA)National Institute for Materials Science (NIMS)Tsukuba305‐0044Japan
| | - Yoshiki Sakuma
- Research Center for Functional MaterialsNational Institute for Materials Science (NIMS)Tsukuba305‐0044Japan
| | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitectonics (WPI‐MANA)National Institute for Materials Science (NIMS)Tsukuba305‐0044Japan
| | - Kazu Suenaga
- Nanomaterials Research InstituteNational Institute of Advanced Industrial Science and TechnologyAIST Central 5Tsukuba305‐8564Japan
| | - Takaaki Taniguchi
- International Center for Materials Nanoarchitectonics (WPI‐MANA)National Institute for Materials Science (NIMS)Tsukuba305‐0044Japan
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14
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Tan CM, Horikawa M, Fukui N, Maeda H, Sasaki S, Tsukagoshi K, Nishihara H. Determination of Chemical Structure of Bis(dithiolato)iron Nanosheet. CHEM LETT 2021. [DOI: 10.1246/cl.200797] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Choon Meng Tan
- Research Center for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Mami Horikawa
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Naoya Fukui
- Research Center for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hiroaki Maeda
- Research Center for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Sono Sasaki
- Faculty of Fibre Science and Engineering, Kyoto Institute of Technology, Kyoto 606-8585, Japan
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Kazuhito Tsukagoshi
- WPI International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
| | - Hiroshi Nishihara
- Research Center for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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15
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Das SR, Wakabayashi K, Tsukagoshi K, Dutta S. Ab-initio investigation of preferential triangular self-formation of oxide heterostructures of monolayer [Formula: see text]. Sci Rep 2020; 10:21737. [PMID: 33303881 PMCID: PMC7729869 DOI: 10.1038/s41598-020-78812-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 12/01/2020] [Indexed: 11/17/2022] Open
Abstract
Triangular growth patterns of pristine two-dimensional (2D) transition metal dichalcogenides (TMDs) are ubiquitous in experiments. Here, we use first-principles calculations to investigate the growth of triangular shaped oxide islands upon layer-by-layer controlled oxidation in monolayer and few-layer [Formula: see text] systems. Pristine 2D TMDs with a trigonal prismatic geometry prefer the triangular growth morphology due to structural stability arising from the edge chalcogen atoms along its three sides. Our ab-initio energetics and thermodynamic study show that, since the Se atoms are more susceptible to oxygen replacement, the preferential oxidation happens along the Se zigzag lines, producing triangular islands of transition metal oxides. The thermodynamic stability arising from the preferential triangular self-formation of TMD based oxide heterostructures and their electronic properties opens a new avenue for their exploration in advanced electronic and optoelectronic devices.
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Affiliation(s)
- Soumya Ranjan Das
- Department of Physics, Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati, Andhra Pradesh 517507 India
| | - Katsunori Wakabayashi
- Department of Nanotechnology for Sustainable Energy, School of Science and Technology, Kwansei Gakuin University, Gakuen 2-1, Sanda, Hyogo 669-1337 Japan
- WPI Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, 305-0044 Japan
| | - Kazuhito Tsukagoshi
- WPI Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, 305-0044 Japan
| | - Sudipta Dutta
- Department of Physics, Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati, Andhra Pradesh 517507 India
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16
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Li M, Lin CY, Chang YM, Yang SH, Lee MP, Chen CF, Lee KC, Yang FS, Chou Y, Lin YC, Ueno K, Shi Y, Chou YC, Tsukagoshi K, Lin YF. Facile and Reversible Carrier-Type Manipulation of Layered MoTe 2 Toward Long-Term Stable Electronics. ACS Appl Mater Interfaces 2020; 12:42918-42924. [PMID: 32864950 DOI: 10.1021/acsami.0c09922] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Flexible manipulation of the carrier transport behaviors in two-dimensional materials determines their values of practical application in logic circuits. Here, we demonstrated the carrier-type manipulation in field-effect transistors (FETs) containing α-phase molybdenum ditelluride (MoTe2) by a rapid thermal annealing (RTA) process in dry air for hole-dominated and electron-beam (EB) treatment for electron-dominated FETs. EB treatment induced a distinct shift of the transfer curve by around 135 V compared with that of the FET-processed RTA treatment, indicating that the carrier density of the EB-treated FET was enhanced by about 1 order of magnitude. X-ray photoelectron spectroscopy analysis revealed that the atomic ratio of Te decreased from 66.4 to 60.8% in the MoTe2 channel after EB treatment. The Fermi level is pinned near the new energy level resulting from the Te vacancies produced by the EB process, leading to the electron-dominant effect of the MoTe2 FET. The electron-dominated MoTe2 FET showed excellent stability for more than 700 days. Thus, we not only realized the reversible modulation of carrier-type in layered MoTe2 FETs but also demonstrated MoTe2 channels with desirable performance, including long-term stability.
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Affiliation(s)
- Mengjiao Li
- Department of Physics, National Chung Hsing University, Taichung 40227, Taiwan
| | - Che-Yi Lin
- Department of Physics, National Chung Hsing University, Taichung 40227, Taiwan
| | - Yuan-Ming Chang
- Department of Physics, National Chung Hsing University, Taichung 40227, Taiwan
| | - Shih-Hsien Yang
- International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of the Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Mu-Pai Lee
- Department of Electrophysics, National Chiao Tung University, Hsinchu 30010, Taiwan
| | - Ciao-Fen Chen
- Department of Physics, National Chung Hsing University, Taichung 40227, Taiwan
| | - Ko-Chun Lee
- Institute of Electronics Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Feng-Shou Yang
- Department of Electrical Engineering and Institute of Electronic Engineering, National Tsing Hua University, Hsinchu 30010, Taiwan
| | - Yi Chou
- Department of Electrophysics, National Chiao Tung University, Hsinchu 30010, Taiwan
| | - Yi-Chun Lin
- Instrument Center, National Chung Hsing University, Taichung 40227, Taiwan
| | - Keiji Ueno
- Department of Chemistry, Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan
| | - Yumeng Shi
- International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of the Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
- Engineering Technology Research Center for 2D Material Information Functional Devices and Systems of Guangdong Province, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
| | - Yi-Chia Chou
- Department of Electrophysics, National Chiao Tung University, Hsinchu 30010, Taiwan
| | - Kazuhito Tsukagoshi
- WPI Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
| | - Yen-Fu Lin
- Department of Physics, National Chung Hsing University, Taichung 40227, Taiwan
- Institute of Nanoscience and Research Center for Sustainable Energy and Nanotechnology, National Chung Hsing University, Taichung 40227, Taiwan
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17
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Kobayashi S, Kaneko S, Kiguchi M, Tsukagoshi K, Nishino T. Tolerance to Stretching in Thiol-Terminated Single-Molecule Junctions Characterized by Surface-Enhanced Raman Scattering. J Phys Chem Lett 2020; 11:6712-6717. [PMID: 32619093 DOI: 10.1021/acs.jpclett.0c01526] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We investigated the change in the metal-molecule interaction in a 1,4-benzenedithiol (BDT) single-molecule junction using a combination of surface-enhanced Raman scattering spectra and current-voltage curves. During the stretching process, the conductance of the junction systematically decreased, accompanied by an increase in the vibrational energy of the CC stretching mode. By analyzing the current-voltage curves and Raman spectra, we found that the interaction between the π orbital of BDT and the electronic states of Au was diminished by the orientation change of BDT during the stretching process. A comparison with a 4,4'-bipyridine single-molecule junction revealed that the reduction of coupling of the Au-S contacts was smaller than that of Au-pyridine contacts. Therefore, the electronic states originating from the contact geometry are responsible for the tolerance to the stretching of thiol-terminated molecular junctions.
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Affiliation(s)
- S Kobayashi
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - S Kaneko
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
- JST PRESTO, 4-1-8 Honcho, Kawaguchi 332-0012, Japan
| | - M Kiguchi
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - K Tsukagoshi
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Tsukuba, Ibaraki 305-0044, Japan
| | - T Nishino
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
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18
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Taniguchi T, Nurdiwijayanto L, Li S, Lim HE, Miyata Y, Lu X, Ma R, Tang DM, Ueda S, Tsukagoshi K, Sasaki T, Osada M. On/Off Boundary of Photocatalytic Activity between Single- and Bilayer MoS 2. ACS Nano 2020; 14:6663-6672. [PMID: 32396324 DOI: 10.1021/acsnano.9b09253] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Molecularly thin two-dimensional (2D) semiconductors are emerging as photocatalysts owing to their layer-number-dependent quantum effects and high charge separation efficiency. However, the correlation among the dimensionality, crystallinity, and photocatalytic activity of such 2D nanomaterials remains unclear. Herein, a Ag photoreduction technique coupled with microscopic analyses is employed to spatially resolve the photocatalytic activity of MoS2 as a model catalyst. Interestingly, we find that only monolayer (1L)-MoS2 is active for a Ag photoreduction reaction. The photocatalytic activity of 1L-MoS2 is enhanced by a built-in electrical field originated from the MoS2/SiO2 interface, instead of by the specific surface structure and quantum electronic state of 1L-MoS2. Furthermore, we observe photocatalytic active sites to be geometrically distributed on triangular 1L-MoS2 crystals, wherein the Ag particles are preferentially deposited on the outermost zigzag edges and defective inner parts of the triangular grains. The degradation of photocatalytic activity and electron mobility with the formation of Mo(VI) species indicates that the species inhibit the in-plane diffusion of the photogenerated electrons to the reductive sites. The monolayer-selectivity, activation, and inactivation mechanisms, unveiled in this work, will offer future directions in designing 2D nanophotocatalysts.
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Affiliation(s)
- Takaaki Taniguchi
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Leanddas Nurdiwijayanto
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Shisheng Li
- International Center for Young Scientists (ICYS), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Hong En Lim
- Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan
| | - Yasumitsu Miyata
- Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan
| | - Xueyi Lu
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Renzhi Ma
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Dang-Ming Tang
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Shigenori Ueda
- Synchrotron X-ray Station at SPring-8, National Institute for Materials Science (NIMS), 1-1-1 Sayo, Hyogo 679-5148, Japan
- Research Center for Advanced Measurement and Characterization, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
| | - Kazuhito Tsukagoshi
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Takayoshi Sasaki
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Minoru Osada
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
- Institute of Materials and Systems for Sustainability, Nagoya University, Furocho, Chikusa-ku, Nagoya 464-8603, Japan
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19
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Liu S, Wang YC, Chang CM, Yasuda T, Fukui N, Maeda H, Long P, Nakazato K, Jian WB, Xie W, Tsukagoshi K, Nishihara H. Solution-processed organometallic quasi-two-dimensional nanosheets as a hole buffer layer for organic light-emitting devices. Nanoscale 2020; 12:6983-6990. [PMID: 32207501 DOI: 10.1039/d0nr00240b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Two-dimensional (2D) vdW materials have been integrated into optoelectronic devices to achieve exceptional functionality. However, the integration of large-area 2D thin films into organic light-emitting devices (OLEDs) remains challenging because of the finite number of inorganic 2D materials and the high-temperature requirements of their deposition process. The construction of 2D organometallic materials holds immense potential because of their solution synthesis and unlimited structural and functional diversity. Here, we report a facile route using an oil-water interfacial coordination reaction between organic ligands and divalent metal ions to synthesize crystalline quasi-2D organometallic bis(dithiolato)nickel (NiDT) nanosheets with a centimeter scale and a tunable thickness. The NiDT nanosheets can be directly integrated into OLEDs for use as a hole buffer layer and a fluorescent mounting medium without the aid of a transfer process. Moreover, OLEDs with NiDT nanosheets show not only comparable efficiency to conventional OLEDs but also prolonged device lifetime by nearly 2 times. These results open up a new dimension to use quasi-2D organometallic nanosheets as functional layers in large-area organic devices.
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Affiliation(s)
- Shihao Liu
- WPI International Center for Materials Nanoarchitectonics (WPI-MANA) & International Center for Young Scientists (ICYS), National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan.
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20
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Wakahara T, Nagaoka K, Nakagawa A, Hirata C, Matsushita Y, Miyazawa K, Ito O, Wada Y, Takagi M, Ishimoto T, Tachikawa M, Tsukagoshi K. One-Dimensional Fullerene/Porphyrin Cocrystals: Near-Infrared Light Sensing through Component Interactions. ACS Appl Mater Interfaces 2020; 12:2878-2883. [PMID: 31845789 DOI: 10.1021/acsami.9b18784] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Recently, organic donor-acceptor (D-A) cocrystals have attracted special interest as functional materials because of their unique chemical and physical properties that are not exhibited by simple mixtures of their components. Herein, we report the preparation of one-dimensional novel D-A cocrystals from C60 and 5,10,15,20-tetrakis(3,5-dimethoxyphenyl)porphyrin (3,5-TPP); these cocrystals have near-infrared (NIR) light-sensing abilities, despite each of their component molecule individually having no NIR light-sensing properties. Micrometer-sized rectangular columnar C60-3,5-TPP cocrystals were produced by a simple liquid-liquid interfacial precipitation method. The cocrystals exhibit a new strong transition in the NIR region indicative of the existence of charge-transfer interactions between C60 and 3,5-TPP in the cocrystals. The C60-3,5-TPP cocrystals showed n-type transport characteristics with NIR light-sensing properties when the cocrystals were incorporated in bottom-gate/bottom-contact organic phototransistors, revealing that organic cocrystals with suitable charge-transfer interaction are useful as functional materials for the creation of novel NIR-light-sensing devices.
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Affiliation(s)
- Takatsugu Wakahara
- Research Center for Functional Materials , National Institute for Materials Science , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
| | - Kahori Nagaoka
- Research Center for Functional Materials , National Institute for Materials Science , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
| | - Akari Nakagawa
- Research Center for Functional Materials , National Institute for Materials Science , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
| | - Chika Hirata
- Research Center for Functional Materials , National Institute for Materials Science , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
| | - Yoshitaka Matsushita
- Research Network and Facility Services Division , National Institute for Materials Science , 1-2-1 Sengen , Tsukuba , Ibaraki 305-0047 , Japan
| | - Kun'ichi Miyazawa
- Department of Industrial Chemistry, Faculty of Engineering , Tokyo University of Science , Tokyo 162-0826 , Japan
| | - Osamu Ito
- Research Center for Functional Materials , National Institute for Materials Science , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
- CarbonPhotoScience Institute , Kita-Nakayama2-1-6 , Izumi-ku, Sendai 981-3215 , Japan
| | - Yoshiki Wada
- Research Center for Functional Materials , National Institute for Materials Science , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
| | - Makito Takagi
- Graduate School of Nanobioscience , Yokohama City University , 22-2 Seto , Kanazawa-ku, Yokohama , Kanagawa 236-0027 , Japan
| | - Takayoshi Ishimoto
- Graduate School of Nanobioscience , Yokohama City University , 22-2 Seto , Kanazawa-ku, Yokohama , Kanagawa 236-0027 , Japan
| | - Masanori Tachikawa
- Graduate School of Nanobioscience , Yokohama City University , 22-2 Seto , Kanazawa-ku, Yokohama , Kanagawa 236-0027 , Japan
| | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
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21
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Yang SH, Lin CY, Chang YM, Li M, Lee KC, Chen CF, Yang FS, Lien CH, Ueno K, Watanabe K, Taniguchi T, Tsukagoshi K, Lin YF. Oxygen-Sensitive Layered MoTe 2 Channels for Environmental Detection. ACS Appl Mater Interfaces 2019; 11:47047-47053. [PMID: 31746187 DOI: 10.1021/acsami.9b15036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The oxygen (O2)-dependent resistance change of multilayered molybdenum ditelluride (MoTe2) channels was characterized. A variation of the channel resistance could reproducibly determine relative O2 content (denoted as the O2 index). We found that Joule heating in a layered MoTe2 field-effect transistor caused the O2 index to decrease drastically from 100 to 12.1% in back gate modulation. Furthermore, Joule heating caused effective O2 desorption from the MoTe2 surface and repeatable O2 detection by multilayered MoTe2 channels was realized. This work not only explored the influence of O2 on the electrical properties of multilayered MoTe2 channels but also revealed that MoTe2 channels are promising for sensing O2 in an environmental condition.
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Affiliation(s)
- Shih-Hsien Yang
- International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics , Shenzhen University , Shenzhen 518060 , China
| | - Che-Yi Lin
- Department of Electrophysics , National Chiao Tung University , Hsinchu 30010 , Taiwan
| | | | | | - Ko-Chun Lee
- Department of Electrical Engineering and Institute of Electronic Engineering , National Tsing Hua University , Hsinchu 30010 , Taiwan
| | | | - Feng-Shou Yang
- Department of Electrical Engineering and Institute of Electronic Engineering , National Tsing Hua University , Hsinchu 30010 , Taiwan
| | - Chen-Hsin Lien
- Department of Electrical Engineering and Institute of Electronic Engineering , National Tsing Hua University , Hsinchu 30010 , Taiwan
| | - Keiji Ueno
- Department of Chemistry, Graduate School of Science and Engineering , Saitama University , Saitama 338-8570 , Japan
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22
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Taniguchi T, Li S, Nurdiwijayanto L, Kobayashi Y, Saito T, Miyata Y, Obata S, Saiki K, Yokoi H, Watanabe K, Taniguchi T, Tsukagoshi K, Ebina Y, Sasaki T, Osada M. Tunable Chemical Coupling in Two-Dimensional van der Waals Electrostatic Heterostructures. ACS Nano 2019; 13:11214-11223. [PMID: 31580052 DOI: 10.1021/acsnano.9b04256] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Heterostructures of two-dimensional (2D) atomic crystals provide fascinating molecular-scale design elements for emergent physical phenomena and functional materials, as integrating distinct monolayers into vertical heterostructures can afford coupling between disparate properties. However, the available examples have been limited to either van der Waals (vdW) or electrostatic (ES) heterostructures that are solely composed of noncharged and charged monolayers, respectively. Here, we propose a "vdW-ES heterostructure" chemical design in which charge-neutral and charged monolayer-building blocks with highly disparate chemical and physical properties are conjugated vertically through asymmetrically charged interfaces. We demonstrate vdW-ES heteroassembly of semiconducting MoS2 and dielectric Ca2Nb3O10- (CNO) monolayers using an amphipathic molecular starch, resulting in the emergence of trion luminescence observed at the lowest energy among MoS2-related materials, probably due to interfacial confinement effects given by vdW-ES dual interactions. In addition, interface engineering leads to tailored exciton of the vdW/ES heterostructures owing to the pronounced dielectric proximity effects, bringing an intriguing interlayer chemistry to modify 2D materials. Furthermore, the current approach was successfully extended to create a graphene/CNO heterostructure, which verifies the versatility of the preparative method.
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Affiliation(s)
- Takaaki Taniguchi
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science(NIMS) , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
| | - Shisheng Li
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science(NIMS) , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
| | - Leanddas Nurdiwijayanto
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science(NIMS) , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
| | - Yu Kobayashi
- Department of Physics , Tokyo Metropolitan University , Hachioji , Tokyo 192-0397 , Japan
| | - Tetsuki Saito
- Department of Physics , Tokyo Metropolitan University , Hachioji , Tokyo 192-0397 , Japan
| | - Yasumitsu Miyata
- Department of Physics , Tokyo Metropolitan University , Hachioji , Tokyo 192-0397 , Japan
| | - Seiji Obata
- Department of Complexity Science and Engineering , Graduate School of Frontier Sciences, The University of Tokyo , Kashiwa , Chiba 277-8561 , Japan
| | - Koichiro Saiki
- Department of Complexity Science and Engineering , Graduate School of Frontier Sciences, The University of Tokyo , Kashiwa , Chiba 277-8561 , Japan
| | - Hiroyuki Yokoi
- Faculty of Advanced Science and Technology , Kumamoto University , Kumamoto 860-8555 , Japan
| | - Kenji Watanabe
- Research Center for Functional Materials , National Institute for Materials Science(NIMS) , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
| | - Takashi Taniguchi
- Research Center for Functional Materials , National Institute for Materials Science(NIMS) , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
| | - Kazuhito Tsukagoshi
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science(NIMS) , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
| | - Yasuo Ebina
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science(NIMS) , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
| | - Takayoshi Sasaki
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science(NIMS) , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
| | - Minoru Osada
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science(NIMS) , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
- Institute of Materials and Systems for Sustainability , Nagoya University , Furocho, Chikusa-ku, Nagoya 464-8603 , Japan
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23
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Da B, Liu J, Harada Y, Cuong NT, Tsukagoshi K, Hu J, Yang L, Ding Z, Yoshikawa H, Tanuma S. Observation of Plasmon Energy Gain for Emitted Secondary Electron in Vacuo. J Phys Chem Lett 2019; 10:5770-5775. [PMID: 31513403 DOI: 10.1021/acs.jpclett.9b02135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Plasmon gain by core-level electrons or elastic electrons observed in past studies seems to be of no practical value in material characterization, mainly because of their ultralow signal intensities. Nevertheless, in the emission spectra of Au samples, we have observed plasmon gain in secondary electrons. The electrons gain energy from surface plasmons after escaping from the surface and thereby only carry surface-plasmon information in the vacuum above the surface. Because the intensity of the emitted SEs is strong, rivaling that of core-level or elastic electrons, the observed phenomenon has in practice the potential to image directly in space the surface plasmon near but exterior to the metal surface.
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Affiliation(s)
- Bo Da
- Research and Services Division of Materials Data and Integrated System , National Institute for Materials Science , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 Japan
- Research Center for Advanced Measurement and Characterization , National Institute for Materials Science , 1-2-1 Sengen , Tsukuba , Ibaraki 305-0047 , Japan
| | - Jiangwei Liu
- Research Center for Functional Materials , National Institute for Materials Science , 1-2-1 Sengen , Tsukuba , Ibaraki 305-0047 , Japan
| | - Yoshitomo Harada
- Research Center for Advanced Measurement and Characterization , National Institute for Materials Science , 1-2-1 Sengen , Tsukuba , Ibaraki 305-0047 , Japan
| | - Nguyen T Cuong
- International Center for Young Scientists , National Institute for Materials Science , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 , Japan
- International Center for Materials Nanoarchitectonics , National Institute for Materials Science (WPI-MANA) , Tsukuba , Ibaraki 305-0044 , Japan
| | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitectonics , National Institute for Materials Science (WPI-MANA) , Tsukuba , Ibaraki 305-0044 , Japan
| | - Jin Hu
- Department of Physics and Institute for Nanoscience and Engineering , University of Arkansas , Fayetteville , Arkansas 72701 , United States
| | - Lihao Yang
- Department of Physics , University of Science and Technology of China , Hefei , Auhui 230026 , P.R. China
| | - Zejun Ding
- Department of Physics , University of Science and Technology of China , Hefei , Auhui 230026 , P.R. China
| | - Hideki Yoshikawa
- Research and Services Division of Materials Data and Integrated System , National Institute for Materials Science , 1-1 Namiki , Tsukuba , Ibaraki 305-0044 Japan
- Research Center for Advanced Measurement and Characterization , National Institute for Materials Science , 1-2-1 Sengen , Tsukuba , Ibaraki 305-0047 , Japan
| | - Shigeo Tanuma
- Research Center for Advanced Measurement and Characterization , National Institute for Materials Science , 1-2-1 Sengen , Tsukuba , Ibaraki 305-0047 , Japan
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24
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Li S, Lin YC, Liu XY, Hu Z, Wu J, Nakajima H, Liu S, Okazaki T, Chen W, Minari T, Sakuma Y, Tsukagoshi K, Suenaga K, Taniguchi T, Osada M. Wafer-scale and deterministic patterned growth of monolayer MoS 2via vapor-liquid-solid method. Nanoscale 2019; 11:16122-16129. [PMID: 31433425 DOI: 10.1039/c9nr04612g] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Vapor transportation is the core process in growing transition-metal dichalcogenides (TMDCs) by chemical vapor deposition (CVD). One inevitable problem is the spatial inhomogeneity of vapors. The non-stoichiometric supply of transition-metal precursors and chalcogens leads to poor control in the products' location, morphology, crystallinity, uniformity and batch to batch reproducibility. The vapor-liquid-solid (VLS) growth method often involves molten precursors (e.g., non-volatile Na2MoO4) at growth temperatures higher than their melting points. The liquid Na2MoO4 can precipitate out solid MoS2 monolayers when saturated with sulfur vapor. Taking advantage of the VLS growth, we attained three kinds of important achievements: (i) a 4-inch-wafer-scale uniform growth of MoS2 flakes on SiO2/Si substrates, (ii) a 2-inch-wafer-scale growth of continuous MoS2 film with the grain size exceeding 100 μm on sapphire substrates, and (iii) a patterned (site-controlled) growth of MoS2 flakes and films. We clarified that the VLS growth thus paves a new way for the high-efficient and scalable synthesis of two-dimensional TMDC monolayers.
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Affiliation(s)
- Shisheng Li
- International Center for Young Scientists (ICYS), National Institute for Materials Science (NIMS), Tsukuba 305-0044, Japan.
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25
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Aiba A, Koizumi R, Tsuruoka T, Terabe K, Tsukagoshi K, Kaneko S, Fujii S, Nishino T, Kiguchi M. Investigation of Ag and Cu Filament Formation Inside the Metal Sulfide Layer of an Atomic Switch Based on Point-Contact Spectroscopy. ACS Appl Mater Interfaces 2019; 11:27178-27182. [PMID: 31276618 DOI: 10.1021/acsami.9b05523] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The atomic switches have attracted wide attention owing to their applications in nonvolatile electric devices. The atomic switch is operated by the formation and dissipation of a metallic filament inside a metal sulfide film, which is controlled by a solid electrochemical reaction. Although the metallic filament is considered to consist of metal atoms, the chemical species of the metallic filament are difficult to be identified due to challenges in observing the metallic filament inside the solid. In this study, we report the investigation on the metallic filament in the atomic switch with metal sulfide based on point-contact spectroscopy (PCS). By cooling the atomic switch, the switch voltage increased to 1 V, which allowed for the PCS measurement. The PCS revealed that the metallic filament was composed of Ag atoms in the case of the Pt/Ag2S/Ag atomic switch. We applied this technique to the Pt/Cu2S/Ag and Pt/Ag2S/Cu atomic switches to uncover the formation process of the metallic filament. In both atomic switches, the chemical species of the metallic filament were Ag. The metal atoms were supplied from both the metal electrode and the sulfide layer.
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Affiliation(s)
- A Aiba
- Department of Chemistry, School of Science , Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama , Meguro-ku, Tokyo 152-8551 , Japan
| | - R Koizumi
- Department of Chemistry, School of Science , Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama , Meguro-ku, Tokyo 152-8551 , Japan
| | - T Tsuruoka
- International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science (NIMS) , 1-1 Tsukuba , Ibaraki 305-0044 , Japan
| | - K Terabe
- International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science (NIMS) , 1-1 Tsukuba , Ibaraki 305-0044 , Japan
| | - K Tsukagoshi
- International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science (NIMS) , 1-1 Tsukuba , Ibaraki 305-0044 , Japan
| | - S Kaneko
- Department of Chemistry, School of Science , Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama , Meguro-ku, Tokyo 152-8551 , Japan
| | - S Fujii
- Department of Chemistry, School of Science , Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama , Meguro-ku, Tokyo 152-8551 , Japan
| | - T Nishino
- Department of Chemistry, School of Science , Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama , Meguro-ku, Tokyo 152-8551 , Japan
| | - M Kiguchi
- Department of Chemistry, School of Science , Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama , Meguro-ku, Tokyo 152-8551 , Japan
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26
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Kaneko S, Montes E, Suzuki S, Fujii S, Nishino T, Tsukagoshi K, Ikeda K, Kano H, Nakamura H, Vázquez H, Kiguchi M. Identifying the molecular adsorption site of a single molecule junction through combined Raman and conductance studies. Chem Sci 2019; 10:6261-6269. [PMID: 31367301 PMCID: PMC6615215 DOI: 10.1039/c9sc00701f] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Accepted: 05/24/2019] [Indexed: 01/01/2023] Open
Abstract
Single-molecule junctions are ideal test beds for investigating the fundamentals of charge transport at the nanoscale. Conducting properties are strongly dependent on the metal-molecule interface geometry, which, however, is very poorly characterized due to numerous experimental challenges. We report on a new methodology for characterizing the adsorption site of single-molecule junctions through the combination of surface enhanced Raman scattering (SERS), current-voltage (I-V) curve measurements, and density functional theory simulations. This new methodology discriminates between three different adsorption sites for benzenedithiol and aminobenzenethiol junctions, which cannot be identified by solo measurements of either SERS or I-V curves. Using this methodology, we determine the interface geometry of these two prototypical molecules at the junction and its time evolution. By modulating the applied voltage, we can change and monitor the distribution of adsorption sites at the junction.
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Affiliation(s)
- Satoshi Kaneko
- Department of Chemistry , School of Science , Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama , Meguro-ku , Tokyo 152-8551 , Japan .
| | - Enrique Montes
- Institute of Physics , Academy of Sciences of the Czech Republic , Cukrovarnicka 10 , Prague CZ-162 00 , Czech Republic .
| | - Sho Suzuki
- Department of Chemistry , School of Science , Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama , Meguro-ku , Tokyo 152-8551 , Japan .
| | - Shintaro Fujii
- Department of Chemistry , School of Science , Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama , Meguro-ku , Tokyo 152-8551 , Japan .
| | - Tomoaki Nishino
- Department of Chemistry , School of Science , Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama , Meguro-ku , Tokyo 152-8551 , Japan .
| | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitectonics , National Institute for Materials Science , Tsukuba , Ibaraki 305-0044 , Japan
| | - Katsuyoshi Ikeda
- Graduate School of Engineering , Nagoya Institute of Technology , Gokiso, Showa , Nagoya 466-8555 , Japan
| | - Hideaki Kano
- Institute of Applied Physics , University of Tsukuba , Tennodai 1-1-1 , Tsukuba 305-8573 , Japan
| | - Hisao Nakamura
- CD-FMat , National Institute of Advanced Industrial Science and Technology (AIST) , Central 2, Umezono 1-1-1 , Tsukuba , Ibaraki 305-8568 , Japan .
| | - Héctor Vázquez
- Institute of Physics , Academy of Sciences of the Czech Republic , Cukrovarnicka 10 , Prague CZ-162 00 , Czech Republic .
| | - Manabu Kiguchi
- Department of Chemistry , School of Science , Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama , Meguro-ku , Tokyo 152-8551 , Japan .
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27
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Thilakan AP, Li JX, Chen TP, Li SS, Chen CW, Osada M, Tsukagoshi K, Sasaki T, Yabushita A, Wu KH, Luo CW. Origin of Extended UV Stability of 2D Atomic Layer Titania-Based Perovskite Solar Cells Unveiled by Ultrafast Spectroscopy. ACS Appl Mater Interfaces 2019; 11:21473-21480. [PMID: 31135127 DOI: 10.1021/acsami.9b02434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The inherent instability of UV-induced degradation in TiO2-based perovskite solar cells was largely improved by replacing the anatase-phase compact TiO2 layer with an atomic sheet transport layer (ASTL) of two-dimensional (2D) Ti1-δO2. The vital role of microscopic carrier dynamics that govern the UV stability of perovskite solar cells was comprehensively examined in this work by performing time-resolved pump-probe spectroscopy. In conventional perovskite solar cells, the presence of a UV-active oxygen vacancy in compact TiO2 prohibits current generation by heavily trapping electrons after UV degradation. Conversely, the dominant vacancy type in the 2D Ti1-δO2 ASTL is a titanium vacancy, which is a shallow acceptor and is not UV-sensitive. Therefore, it significantly suppresses carrier recombination and extends UV stability in perovskite solar cells with a 2D Ti1-δO2 ASTL. Other carrier dynamics, such as electron diffusion, electron injection, and hot hole transfer processes, were found to be less affected by UV irradiation. Quantitative pump-probe data clearly show a correlation between the carrier dynamics and UV aging of perovskite solar cells, thus providing a profound insight into the factors driving UV-induced degradation in perovskite solar cells and the origin of its performance.
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Affiliation(s)
| | | | | | | | - Chun-Wei Chen
- Taiwan Consortium of Emergent Crystalline Materials (TCECM) , Ministry of Science and Technology , Taipei 10617 , Taiwan
| | - Minoru Osada
- Institute of Materials and Systems for Sustainability (iMaSS), Department of Materials Chemistry , Nagoya University , Nagoya 464-8603 , Japan
- The International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science , Tsukuba 305-0044 , Japan
| | - Kazuhito Tsukagoshi
- The International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science , Tsukuba 305-0044 , Japan
| | - Takayoshi Sasaki
- The International Center for Materials Nanoarchitectonics (WPI-MANA) , National Institute for Materials Science , Tsukuba 305-0044 , Japan
| | | | | | - Chih-Wei Luo
- Taiwan Consortium of Emergent Crystalline Materials (TCECM) , Ministry of Science and Technology , Taipei 10617 , Taiwan
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28
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Kobayashi S, Kaneko S, Fujii S, Nishino T, Tsukagoshi K, Kiguchi M. Stretch dependent electronic structure and vibrational energy of the bipyridine single molecule junction. Phys Chem Chem Phys 2019; 21:16910-16913. [DOI: 10.1039/c9cp01442j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Change in the molecular orbital energy and vibrational energy of the bipyridine single molecule junction as a function of stretch distance.
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Affiliation(s)
- S. Kobayashi
- Department of Chemistry
- Tokyo Institute of Technology
- Meguro-ku
- Japan
| | - S. Kaneko
- Department of Chemistry
- Tokyo Institute of Technology
- Meguro-ku
- Japan
| | - S. Fujii
- Department of Chemistry
- Tokyo Institute of Technology
- Meguro-ku
- Japan
| | - T. Nishino
- Department of Chemistry
- Tokyo Institute of Technology
- Meguro-ku
- Japan
| | - K. Tsukagoshi
- International Center for Materials Nanoarchitectonics (WPI-MANA)
- National Institute for Materials Science
- Tsukuba
- Japan
| | - M. Kiguchi
- Department of Chemistry
- Tokyo Institute of Technology
- Meguro-ku
- Japan
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29
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Yamamoto M, Ueno K, Tsukagoshi K. Pronounced photogating effect in atomically thin WSe 2 with a self-limiting surface oxide layer. Appl Phys Lett 2018. [PMID: 0 DOI: 10.1063/1.5030525] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Affiliation(s)
- Mahito Yamamoto
- International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan
| | - Keiji Ueno
- Department of Chemistry, Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan
| | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan
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30
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Chang YM, Yang SH, Lin CY, Chen CH, Lien CH, Jian WB, Ueno K, Suen YW, Tsukagoshi K, Lin YF. Reversible and Precisely Controllable p/n-Type Doping of MoTe 2 Transistors through Electrothermal Doping. Adv Mater 2018; 30:e1706995. [PMID: 29430746 DOI: 10.1002/adma.201706995] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Indexed: 06/08/2023]
Abstract
Precisely controllable and reversible p/n-type electronic doping of molybdenum ditelluride (MoTe2 ) transistors is achieved by electrothermal doping (E-doping) processes. E-doping includes electrothermal annealing induced by an electric field in a vacuum chamber, which results in electron (n-type) doping and exposure to air, which induces hole (p-type) doping. The doping arises from the interaction between oxygen molecules or water vapor and defects of tellurium at the MoTe2 surface, and allows the accurate manipulation of p/n-type electrical doping of MoTe2 transistors. Because no dopant or special gas is used in the E-doping processes of MoTe2 , E-doping is a simple and efficient method. Moreover, through exact manipulation of p/n-type doping of MoTe2 transistors, quasi-complementary metal oxide semiconductor adaptive logic circuits, such as an inverter, not or gate, and not and gate, are successfully fabricated. The simple method, E-doping, adopted in obtaining p/n-type doping of MoTe2 transistors undoubtedly has provided an approach to create the electronic devices with desired performance.
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Affiliation(s)
- Yuan-Ming Chang
- Department of Physics, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Shih-Hsien Yang
- Department of Electrical Engineering and Institute of Electronic Engineering, National Tsing Hua University, Hsinchu, 30071, Taiwan
| | - Che-Yi Lin
- Department of Electrophysics, National Chiao Tung University, Hsinchu, 30010, Taiwan
| | - Chang-Hung Chen
- Department of Physics, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Chen-Hsin Lien
- Department of Electrical Engineering and Institute of Electronic Engineering, National Tsing Hua University, Hsinchu, 30071, Taiwan
| | - Wen-Bin Jian
- Department of Electrophysics, National Chiao Tung University, Hsinchu, 30010, Taiwan
| | - Keiji Ueno
- Department of Chemistry, Graduate School of Science and Engineering, Saitama University, Saitama, 338-8570, Japan
| | - Yuen-Wuu Suen
- Department of Physics, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Kazuhito Tsukagoshi
- WPI Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, 305-0044, Japan
| | - Yen-Fu Lin
- Department of Physics, National Chung Hsing University, Taichung, 40227, Taiwan
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31
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Aiba A, Kaneko S, Fujii S, Nishino T, Tsukagoshi K, Kiguchi M. In situ observation of the formation process for free-standing Au nanowires with a scanning electron microscope. Nanotechnology 2017; 28:105707. [PMID: 28169228 DOI: 10.1088/1361-6528/aa59f0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We have developed a simultaneous electronic and structural characterization method for studying the formation process for Au nanowires. The method is based on two-probe electronic transport measurement of free-standing Au nanowires and simultaneous structural characterization using scanning electron microscopy (SEM). We measured the electronic currents during the electromigration (EM)-induced narrowing process for the free-standing Au nanowires. A free-standing Au nanowire with a desired conductance value was fabricated by EM. Simultaneous SEM and conductance measurements revealed the EM-induced narrowing process for the Au wires, in which material transfer in the nanowires caused growth towards the positively biased electrode and contact failure at the negatively biased electrode. The narrowed free-standing Au nanowires were stable and could be maintained for more than 10 h without their conductance changing. These results indicate the high stability of the EM-processed Au nanowires compared to Au nanowires fabricated by mechanical elongation or the breaking of Au nanocontacts.
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Affiliation(s)
- Akira Aiba
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 W4-10, Ookayama, Meguro-ku, Tokyo 152-8551, Japan
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32
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Hayasaka M, Ogasawara H, Hotta Y, Tsukagoshi K, Kimura O, Kura T, Tarumi T, Muramatsu H, Endo T. Nutritional assessment using stable isotope ratios of carbon and nitrogen in the scalp hair of geriatric patients who received enteral and parenteral nutrition formulas. Clin Nutr 2016; 36:1661-1668. [PMID: 27847116 DOI: 10.1016/j.clnu.2016.10.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 10/14/2016] [Accepted: 10/17/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND & AIMS The δ13C and δ15N values in the scalp hair of geriatric patients in Japan who received the enteral or parenteral nutrition formula were measured to assess nutritional status. METHODS The relations among δ13C, δ15N, calorie intake, BMI, albumin concentration, total cholesterol (T-CHO) and geriatric nutritional risk index (GNRI) in the patients were investigated. Furthermore, the enrichment of δ13C and δ15N from the nutrients to the hair was investigated. RESULTS The δ13C values in the hair of patients who received enteral nutrition decreased with decreases in the calories received, while the δ15N values increased, suggesting malnutrition in some patients with a low calorie intake due to a negative nitrogen balance. The distribution of patients with a low calorie intake (below 20 kcal/kg/day) when δ13C was plotted against δ15N differed from that of control subjects, but the distribution of patients with a high calorie intake (above 20 kcal/kg/day) was similar to that of control subjects. No significant differences were observed in BMI, albumin concentration, T-CHO or GNRI between the low and high calorie groups. The enrichment of δ13C and δ15N from the enteral nutrients to the hair were inversely correlated with the δ13C and δ15N in the enteral nutrients. The enrichment levels of δ13C and δ15N tended to be higher and lower, respectively, in the high calorie group. On the other hand, the δ13C and δ15N values in the hair of patients who received parenteral nutrition were higher and lower than those in the control subjects and in the patients who received enteral nutrition, respectively, reflecting the higher δ13C and lower δ15N contents of the parenteral nutrients. CONCLUSIONS The δ13C and δ15N values in the hair of patients who received enteral nutrition may be effective indicators for evaluating the long-term nutritional status of geriatric patients. A calorie intake of 20 kcal/kg/day may be a cut-off value for malnutrition in Japanese geriatric patients receiving enteral nutrition. However, caution is necessary when dealing with patients switching from parental nutrition as parenteral nutrition resulted in different changes in δ13C and δ15N. The enrichment levels of δ13C and δ15N from the enteral nutrients to the hair may be inversely correlated with the δ13C and δ15N values of enteral nutrients and vary according to the calorie intake.
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Affiliation(s)
- M Hayasaka
- Sapporo Higashi-Tokushukai Hospital, N33-E14, Higashi-ku, Sapporo, Hokkaido 065-0033, Japan
| | - H Ogasawara
- Sapporo Minami-Seishu Hospital, 1-2-20, Satozuka, Kiyota-Ku, Sapporo, Hokkaido 004-0801, Japan
| | - Y Hotta
- Hokusei Hospital, W3-2-10, Sinkawa, Kita-Ku, Sapporo, Hokkaido 001-0933, Japan
| | - K Tsukagoshi
- Hijirigaoka Hospital, 214-22, Funaoka, Date, Hokkaido 052-0014, Japan
| | - O Kimura
- School of Pharmaceutical Science, Health Sciences University of Hokkaido, 1757 Kanazawa, Ishikari-Tobetsu, Hokkaido 061-0293, Japan
| | - T Kura
- Naganuma Municipal Hospital, 2-2-1 Chuo, Naganuma, Yubari, Hokkaido 069-1332, Japan
| | - T Tarumi
- Hokusei Hospital, W3-2-10, Sinkawa, Kita-Ku, Sapporo, Hokkaido 001-0933, Japan
| | - H Muramatsu
- Rumoi City Hospital, 2-16 Shinonome, Rumoi, Hokkaido 077-8511, Japan
| | - T Endo
- School of Pharmaceutical Science, Health Sciences University of Hokkaido, 1757 Kanazawa, Ishikari-Tobetsu, Hokkaido 061-0293, Japan.
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33
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Suga H, Suzuki H, Shinomura Y, Kashiwabara S, Tsukagoshi K, Shimizu T, Naitoh Y. Highly stable, extremely high-temperature, nonvolatile memory based on resistance switching in polycrystalline Pt nanogaps. Sci Rep 2016; 6:34961. [PMID: 27725705 PMCID: PMC5057135 DOI: 10.1038/srep34961] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 09/22/2016] [Indexed: 11/30/2022] Open
Abstract
Highly stable, nonvolatile, high-temperature memory based on resistance switching was realized using a polycrystalline platinum (Pt) nanogap. The operating temperature of the memory can be drastically increased by the presence of a sharp-edged Pt crystal facet in the nanogap. A short distance between the facet edges maintains the nanogap shape at high temperature, and the sharp shape of the nanogap densifies the electric field to maintain a stable current flow due to field migration. Even at 873 K, which is a significantly higher temperature than feasible for conventional semiconductor memory, the nonvolatility of the proposed memory allows stable ON and OFF currents, with fluctuations of less than or equal to 10%, to be maintained for longer than eight hours. An advantage of this nanogap scheme for high-temperature memory is its secure operation achieved through the assembly and disassembly of a Pt needle in a high electric field.
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Affiliation(s)
- Hiroshi Suga
- Department of Technology of Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan
| | - Hiroya Suzuki
- Department of Technology of Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan
| | - Yuma Shinomura
- Department of Technology of Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan
| | - Shota Kashiwabara
- Department of Technology of Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan
| | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, Ibaraki 305-0044, Japan
| | - Tetsuo Shimizu
- Nanomaterials Research Institute, Department of Materials and Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Higashi 1-1-1 Tsukuba, Ibaraki 305-8562, Japan
| | - Yasuhisa Naitoh
- Nanoelectronics Research Institute, Department of Electronics and Manufacturing, National Institute of Advanced Industrial Science and Technology (AIST), Higashi 1-1-1 Tsukuba, Ibaraki 305-8562, Japan
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34
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Takahashi R, Kaneko S, Marqués-González S, Fujii S, Nishino T, Tsukagoshi K, Kiguchi M. Determination of the number of atoms present in nano contact based on shot noise measurements with highly stable nano-fabricated electrodes. Nanotechnology 2016; 27:295203. [PMID: 27291763 DOI: 10.1088/0957-4484/27/29/295203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A highly stable experimental setup was developed for the measurement of shot noise in atomic contacts and molecular junctions to determine the number of atoms or molecules present. The use of a nano-fabricated mechanically controllable break junction (MCBJ) electrode improved the overall stability of the experimental setup. The improved stability of the system and optimization of measurement system enabled us to comprehensively investigate the shot noise as well as charge transport properties in Au atomic contacts and molecular junctions. We present a solid proof that the number of atoms (cross sectional atom) in the Au atomic contacts was exactly one. In the atomic contacts, contribution from the additional channels was under the detection limit. Furthermore, the effect of molecular adsorption on the charge transport in the Au atomic contact was investigated. Additional transport channels were opened by exposing pyrazine molecules to the Au contacts, which gave rise to an increase in the Fano factor in the shot noise.
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Affiliation(s)
- Ryoji Takahashi
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 W4-10, Ookayama, Meguro-ku, Tokyo 152-8551, Japan
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35
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Nakaharai S, Yamamoto M, Ueno K, Tsukagoshi K. Carrier Polarity Control in α-MoTe2 Schottky Junctions Based on Weak Fermi-Level Pinning. ACS Appl Mater Interfaces 2016; 8:14732-14739. [PMID: 27203118 DOI: 10.1021/acsami.6b02036] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The polarity of the charge carriers injected through Schottky junctions of α-phase molybdenum ditelluride (α-MoTe2) and various metals was characterized. We found that the Fermi-level pinning in the metal/α-MoTe2 Schottky junction is so weak that the polarity of the carriers (electron or hole) injected from the junction can be controlled by the work function of the metals, in contrast to other transition metal dichalcogenides such as MoS2. From the estimation of the Schottky barrier heights, we obtained p-type carrier (hole) injection from a Pt/α-MoTe2 junction with a Schottky barrier height of 40 meV at the valence band edge. n-Type carrier (electron) injection from Ti/α-MoTe2 and Ni/α-MoTe2 junctions was also observed with Schottky barrier heights of 50 and 100 meV, respectively, at the conduction band edge. In addition, enhanced ambipolarity was demonstrated in a Pt-Ti hybrid contact with a unique structure specially designed for polarity-reversible transistors, in which Pt and Ti electrodes were placed in parallel for injecting both electrons and holes.
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Affiliation(s)
- Shu Nakaharai
- WPI Center for Materials Nanoarchitechtonics, National Institute for Materials Science , Tsukuba 305-0044, Japan
| | - Mahito Yamamoto
- WPI Center for Materials Nanoarchitechtonics, National Institute for Materials Science , Tsukuba 305-0044, Japan
| | - Keiji Ueno
- Department of Chemistry, Graduate School of Science and Engineering, Saitama University , Saitama 338-8570, Japan
| | - Kazuhito Tsukagoshi
- WPI Center for Materials Nanoarchitechtonics, National Institute for Materials Science , Tsukuba 305-0044, Japan
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36
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Yamamoto M, Nakaharai S, Ueno K, Tsukagoshi K. Self-Limiting Oxides on WSe2 as Controlled Surface Acceptors and Low-Resistance Hole Contacts. Nano Lett 2016; 16:2720-7. [PMID: 26963588 DOI: 10.1021/acs.nanolett.6b00390] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Transition metal oxides show much promise as effective p-type contacts and dopants in electronics based on transition metal dichalcogenides. Here we report that atomically thin films of under-stoichiometric tungsten oxides (WOx with x < 3) grown on tungsten diselenide (WSe2) can be used as both controlled charge transfer dopants and low-barrier contacts for p-type WSe2 transistors. Exposure of atomically thin WSe2 transistors to ozone (O3) at 100 °C results in self-limiting oxidation of the WSe2 surfaces to conducting WOx films. WOx-covered WSe2 is highly hole-doped due to surface electron transfer from the underlying WSe2 to the high electron affinity WOx. The dopant concentration can be reduced by suppressing the electron affinity of WOx by air exposure, but exposure to O3 at room temperature leads to the recovery of the electron affinity. Hence, surface transfer doping with WOx is virtually controllable. Transistors based on WSe2 covered with WOx show only p-type conductions with orders of magnitude better on-current, on/off current ratio, and carrier mobility than without WOx, suggesting that the surface WOx serves as a p-type contact with a low hole Schottky barrier. Our findings point to a simple and effective strategy for creating p-type devices based on two-dimensional transition metal dichalcogenides with controlled dopant concentrations.
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Affiliation(s)
- Mahito Yamamoto
- WPI Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science , Tsukuba, Ibaraki 305-0044, Japan
| | - Shu Nakaharai
- WPI Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science , Tsukuba, Ibaraki 305-0044, Japan
| | - Keiji Ueno
- Department of Chemistry, Graduate School of Science and Engineering, Saitama University , Saitama 338-8570, Japan
| | - Kazuhito Tsukagoshi
- WPI Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science , Tsukuba, Ibaraki 305-0044, Japan
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37
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Kim HJ, Osada M, Ebina Y, Sugimoto W, Tsukagoshi K, Sasaki T. Hunting for Monolayer Oxide Nanosheets and Their Architectures. Sci Rep 2016; 6:19402. [PMID: 26806214 PMCID: PMC4726153 DOI: 10.1038/srep19402] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 12/07/2015] [Indexed: 02/03/2023] Open
Abstract
In two-dimensional materials, thickness identification with a sufficient characterization range is essential to fundamental study and practical applications. Here, we report a universal optical method for rapid and reliable identification of single- to quindecuple-layers in oxide nanosheets (Ti0.87O2, Ca2Nb3O10, Ca2NaNb4O13). Because of their wide bandgap nature (Eg = ∼4 eV) and zero opacity, most oxide nanosheets exhibit a weak white-light contrast (<1.5%), which precludes optical identification. Through a systematic study of the optical reflectivity of Ti0.87O2 nanosheets on SiO2/Si substrates, we show that the use of thinner SiO2 (∼100 nm) offers optimum visualization conditions with a contrast of >5%; the contrast is a nonmonotonic function of wavelength and changes its sign at ≈550 nm; the nanosheets are brighter than the substrate at short wavelengths and darker at long ones. Such a nonmonotonic optical response is common to semiconducting oxide nanosheets, including Ca2Nb3O10 and Ca2NaNb4O13. The optical contrast differences between the substrates and nanosheets with different numbers of layers were collected, serving as a standard reference from which the number of layers can be determined by optical microscopy. Our method will facilitate the thickness-dependent study of various oxide nanosheets and their architectures, as well as expedite research toward practical applications.
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Affiliation(s)
- Hyung-Jun Kim
- International Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, 305-0044, Japan
| | - Minoru Osada
- International Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, 305-0044, Japan
| | - Yasuo Ebina
- International Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, 305-0044, Japan
| | - Wataru Sugimoto
- Materials and Chemical Engineering, Shinshu University, Ueda, Nagano 386-8567, Japan
| | - Kazuhito Tsukagoshi
- International Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, 305-0044, Japan
| | - Takayoshi Sasaki
- International Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, 305-0044, Japan
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38
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Kaneko S, Murai D, Marqués-González S, Nakamura H, Komoto Y, Fujii S, Nishino T, Ikeda K, Tsukagoshi K, Kiguchi M. Site-Selection in Single-Molecule Junction for Highly Reproducible Molecular Electronics. J Am Chem Soc 2016; 138:1294-300. [PMID: 26728229 DOI: 10.1021/jacs.5b11559] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Adsorption sites of molecules critically determine the electric/photonic properties and the stability of heterogeneous molecule-metal interfaces. Then, selectivity of adsorption site is essential for development of the fields including organic electronics, catalysis, and biology. However, due to current technical limitations, site-selectivity, i.e., precise determination of the molecular adsorption site, remains a major challenge because of difficulty in precise selection of meaningful one among the sites. We have succeeded the single site-selection at a single-molecule junction by performing newly developed hybrid technique: simultaneous characterization of surface enhanced Raman scattering (SERS) and current-voltage (I-V) measurements. The I-V response of 1,4-benzenedithiol junctions reveals the existence of three metastable states arising from different adsorption sites. Notably, correlated SERS measurements show selectivity toward one of the adsorption sites: "bridge sites". This site-selectivity represents an essential step toward the reliable integration of individual molecules on metallic surfaces. Furthermore, the hybrid spectro-electric technique reveals the dependence of the SERS intensity on the strength of the molecule-metal interaction, showing the interdependence between the optical and electronic properties in single-molecule junctions.
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Affiliation(s)
- Satoshi Kaneko
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Daigo Murai
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Santiago Marqués-González
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Hisao Nakamura
- National Institute of Advanced Industrial Science and Technology (AIST) , Central 2, Umezono 1-1-1, Tsukuba, Ibaraki 305-8568, Japan
| | - Yuki Komoto
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Shintaro Fujii
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Tomoaki Nishino
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Katsuyoshi Ikeda
- Department of Mechanical Engineering, Nagoya Institute of Technology , Gokiso, Showa, Nagoya 466-8555, Japan
| | - Kazuhito Tsukagoshi
- WPI Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science , Tsukuba, Ibaraki 305-0044, Japan
| | - Manabu Kiguchi
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology , 2-12-1 W4-10 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
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Li SL, Tsukagoshi K, Orgiu E, Samorì P. Charge transport and mobility engineering in two-dimensional transition metal chalcogenide semiconductors. Chem Soc Rev 2016; 45:118-51. [DOI: 10.1039/c5cs00517e] [Citation(s) in RCA: 341] [Impact Index Per Article: 42.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
This review presents recent progress on charge transport properties, carrier scattering mechanisms, and carrier mobility engineering of two-dimensional transition metal chalcogenides.
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Affiliation(s)
- Song-Lin Li
- Institut de Science et d'Ingénierie Supramoléculaires (ISIS) and International Center for Frontier Research in Chemistry (icFRC)
- Université de Strasbourg and Centre National de la Recherche Scientifique (CNRS)
- Strasbourg 67083
- France
| | - Kazuhito Tsukagoshi
- World Premier International Center for Materials Nanoarchitechtonics (WPI-MANA)
- National Institute for Materials Science (NIMS)
- Tsukuba
- Japan
| | - Emanuele Orgiu
- Institut de Science et d'Ingénierie Supramoléculaires (ISIS) and International Center for Frontier Research in Chemistry (icFRC)
- Université de Strasbourg and Centre National de la Recherche Scientifique (CNRS)
- Strasbourg 67083
- France
| | - Paolo Samorì
- Institut de Science et d'Ingénierie Supramoléculaires (ISIS) and International Center for Frontier Research in Chemistry (icFRC)
- Université de Strasbourg and Centre National de la Recherche Scientifique (CNRS)
- Strasbourg 67083
- France
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40
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Lin YF, Xu Y, Lin CY, Suen YW, Yamamoto M, Nakaharai S, Ueno K, Tsukagoshi K. Origin of Noise in Layered MoTe₂ Transistors and its Possible Use for Environmental Sensors. Adv Mater 2015; 27:6612-6619. [PMID: 26414685 DOI: 10.1002/adma.201502677] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 07/27/2015] [Indexed: 06/05/2023]
Abstract
Low-frequency current fluctuations are monitored and the mechanism of electric noise investigated in layered 2H-type α-molybdenum ditelluride transistors. The charge transport mechanism of electric noise in atomically thin transition-metal dichalcogenides is studied under different environments; the development of a new sensing functionality may be stimulated.
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Affiliation(s)
- Yen-Fu Lin
- Department of Physics, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Yong Xu
- Department of Energy and Materials Engineering, Dongguk University, Seoul, 100-715, Korea
| | - Che-Yi Lin
- Department of Physics, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Yuen-Wuu Suen
- Department of Physics, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Mahito Yamamoto
- WPI Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, 305-0044, Japan
| | - Shu Nakaharai
- WPI Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, 305-0044, Japan
| | - Keiji Ueno
- Department of Chemistry, Graduate School of Science and Engineering, Saitama University, Saitama, 338-8570, Japan
| | - Kazuhito Tsukagoshi
- WPI Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, 305-0044, Japan
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41
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Matsuo S, Takeshita S, Tanaka T, Nakaharai S, Tsukagoshi K, Moriyama T, Ono T, Kobayashi K. Edge mixing dynamics in graphene p-n junctions in the quantum Hall regime. Nat Commun 2015; 6:8066. [PMID: 26337445 PMCID: PMC4569692 DOI: 10.1038/ncomms9066] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 07/13/2015] [Indexed: 11/09/2022] Open
Abstract
Massless Dirac electron systems such as graphene exhibit a distinct half-integer quantum Hall effect, and in the bipolar transport regime co-propagating edge states along the p–n junction are realized. Additionally, these edge states are uniformly mixed at the junction, which makes it a unique structure to partition electrons in these edge states. Although many experimental works have addressed this issue, the microscopic dynamics of electron partition in this peculiar structure remains unclear. Here we performed shot-noise measurements on the junction in the quantum Hall regime as well as at zero magnetic field. We found that, in sharp contrast with the zero-field case, the shot noise in the quantum Hall regime is finite in the bipolar regime, but is strongly suppressed in the unipolar regime. Our observation is consistent with the theoretical prediction and gives microscopic evidence that the edge states are uniquely mixed along the p–n junction. A graphene p–n junction can be created by connecting electrical gates that generate electron-doped and hole-doped areas in a flake. Here, the authors use shot-noise measurements to provide microscopic evidence that edge states are uniquely mixed along the junction in the quantum Hall regime.
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Affiliation(s)
- Sadashige Matsuo
- Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan.,Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Shunpei Takeshita
- Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Takahiro Tanaka
- Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | | | | | - Takahiro Moriyama
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Teruo Ono
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Kensuke Kobayashi
- Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
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42
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Matsuo S, Nakaharai S, Komatsu K, Tsukagoshi K, Moriyama T, Ono T, Kobayashi K. Parity effect of bipolar quantum Hall edge transport around graphene antidots. Sci Rep 2015; 5:11723. [PMID: 26122468 PMCID: PMC4485210 DOI: 10.1038/srep11723] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 06/03/2015] [Indexed: 11/09/2022] Open
Abstract
Parity effect, which means that even-odd property of an integer physical parameter results in an essential difference, ubiquitously appears and enables us to grasp its physical essence as the microscopic mechanism is less significant in coarse graining. Here we report a new parity effect of quantum Hall edge transport in graphene antidot devices with pn junctions (PNJs). We found and experimentally verified that the bipolar quantum Hall edge transport is drastically affected by the parity of the number of PNJs. This parity effect is universal in bipolar quantum Hall edge transport of not only graphene but also massless Dirac electron systems. These results offer a promising way to design electron interferometers in graphene.
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Affiliation(s)
- Sadashige Matsuo
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
- Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | | | | | | | - Takahiro Moriyama
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Teruo Ono
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Kensuke Kobayashi
- Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
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Nakaharai S, Yamamoto M, Ueno K, Lin YF, Li SL, Tsukagoshi K. Electrostatically Reversible Polarity of Ambipolar α-MoTe2 Transistors. ACS Nano 2015; 9:5976-5983. [PMID: 25988597 DOI: 10.1021/acsnano.5b00736] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A doping-free transistor made of ambipolar α-phase molybdenum ditelluride (α-MoTe2) is proposed in which the transistor polarity (p-type and n-type) is electrostatically controlled by dual top gates. The voltage signal in one of the gates determines the transistor polarity, while the other gate modulates the drain current. We demonstrate the transistor operation experimentally, with electrostatically controlled polarity of both p- and n-type in a single transistor.
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Affiliation(s)
- Shu Nakaharai
- †WPI Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
| | - Mahito Yamamoto
- †WPI Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
| | - Keiji Ueno
- ‡Department of Chemistry, Graduate School of Science and Engineering, Saitama University, Saitama 338-8570, Japan
| | - Yen-Fu Lin
- †WPI Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
- §Department of Physics, National Chung Hsing University, Taichung 40227, Taiwan
| | - Song-Lin Li
- †WPI Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
| | - Kazuhito Tsukagoshi
- †WPI Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
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44
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Yamamoto M, Dutta S, Aikawa S, Nakaharai S, Wakabayashi K, Fuhrer MS, Ueno K, Tsukagoshi K. Self-limiting layer-by-layer oxidation of atomically thin WSe2. Nano Lett 2015; 15:2067-73. [PMID: 25646637 DOI: 10.1021/nl5049753] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Growth of a uniform oxide film with a tunable thickness on two-dimensional transition metal dichalcogenides is of great importance for electronic and optoelectronic applications. Here we demonstrate homogeneous surface oxidation of atomically thin WSe2 with a self-limiting thickness from single- to trilayers. Exposure to ozone (O3) below 100 °C leads to the lateral growth of tungsten oxide selectively along selenium zigzag-edge orientations on WSe2. With further O3 exposure, the oxide regions coalesce and oxidation terminates leaving a uniform thickness oxide film on top of unoxidized WSe2. At higher temperatures, oxidation evolves in the layer-by-layer regime up to trilayers. The oxide films formed on WSe2 are nearly atomically flat. Using photoluminescence and Raman spectroscopy, we find that the underlying single-layer WSe2 is decoupled from the top oxide but hole-doped. Our findings offer a new strategy for creating atomically thin heterostructures of semiconductors and insulating oxides with potential for applications in electronic devices.
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Affiliation(s)
- Mahito Yamamoto
- WPI Center for Materials Nanoarchitechtonics (WPI-MANA) and ‡International Center for Young Scientists, National Institute for Materials Science , Tsukuba, Ibaraki 305-0044, Japan
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45
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Li SL, Komatsu K, Nakaharai S, Lin YF, Yamamoto M, Duan X, Tsukagoshi K. Thickness scaling effect on interfacial barrier and electrical contact to two-dimensional MoS2 layers. ACS Nano 2014; 8:12836-12842. [PMID: 25470503 DOI: 10.1021/nn506138y] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Understanding the interfacial electrical properties between metallic electrodes and low-dimensional semiconductors is essential for both fundamental science and practical applications. Here we report the observation of thickness reduction induced crossover of electrical contact at Au/MoS2 interfaces. For MoS2 thicker than 5 layers, the contact resistivity slightly decreases with reducing MoS2 thickness. By contrast, the contact resistivity sharply increases with reducing MoS2 thickness below 5 layers, mainly governed by the quantum confinement effect. We find that the interfacial potential barrier can be finely tailored from 0.3 to 0.6 eV by merely varying MoS2 thickness. A full evolution diagram of energy level alignment is also drawn to elucidate the thickness scaling effect. The finding of tailoring interfacial properties with channel thickness represents a useful approach controlling the metal/semiconductor interfaces which may result in conceptually innovative functionalities.
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Affiliation(s)
- Song-Lin Li
- WPI Center for Materials Nanoarchitechtonics and ‡International Center for Young Scientist, National Institute for Materials Science , Tsukuba, Ibaraki 305-0044, Japan
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46
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Sun H, Wang Q, Li Y, Lin YF, Wang Y, Yin Y, Xu Y, Liu C, Tsukagoshi K, Pan L, Wang X, Hu Z, Shi Y. Boost up carrier mobility for ferroelectric organic transistor memory via buffering interfacial polarization fluctuation. Sci Rep 2014; 4:7227. [PMID: 25428665 PMCID: PMC4245676 DOI: 10.1038/srep07227] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 11/11/2014] [Indexed: 11/14/2022] Open
Abstract
Ferroelectric organic field-effect transistors (Fe-OFETs) have been attractive for a variety of non-volatile memory device applications. One of the critical issues of Fe-OFETs is the improvement of carrier mobility in semiconducting channels. In this article, we propose a novel interfacial buffering method that inserts an ultrathin poly(methyl methacrylate) (PMMA) between ferroelectric polymer and organic semiconductor layers. A high field-effect mobility (μFET) up to 4.6 cm2 V−1 s−1 is obtained. Subsequently, the programming process in our Fe-OFETs is mainly dominated by the switching between two ferroelectric polarizations rather than by the mobility-determined charge accumulation at the channel. Thus, the “reading” and “programming” speeds are significantly improved. Investigations show that the polarization fluctuation at semiconductor/insulator interfaces, which affect the charge transport in conducting channels, can be suppressed effectively using our method.
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Affiliation(s)
- Huabin Sun
- School of Electronic Science and Engineering, Collaborative Center of Advanced Microstructures, National Laboratory of Solid-State Microstructures, Nanjing University, Nanjing 210093, China
| | - Qijing Wang
- School of Electronic Science and Engineering, Collaborative Center of Advanced Microstructures, National Laboratory of Solid-State Microstructures, Nanjing University, Nanjing 210093, China
| | - Yun Li
- School of Electronic Science and Engineering, Collaborative Center of Advanced Microstructures, National Laboratory of Solid-State Microstructures, Nanjing University, Nanjing 210093, China
| | - Yen-Fu Lin
- International Centre for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
| | - Yu Wang
- School of Electronic Science and Engineering, Collaborative Center of Advanced Microstructures, National Laboratory of Solid-State Microstructures, Nanjing University, Nanjing 210093, China
| | - Yao Yin
- School of Electronic Science and Engineering, Collaborative Center of Advanced Microstructures, National Laboratory of Solid-State Microstructures, Nanjing University, Nanjing 210093, China
| | - Yong Xu
- International Centre for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
| | - Chuan Liu
- International Centre for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
| | - Kazuhito Tsukagoshi
- International Centre for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
| | - Lijia Pan
- School of Electronic Science and Engineering, Collaborative Center of Advanced Microstructures, National Laboratory of Solid-State Microstructures, Nanjing University, Nanjing 210093, China
| | - Xizhang Wang
- Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Zheng Hu
- Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Yi Shi
- School of Electronic Science and Engineering, Collaborative Center of Advanced Microstructures, National Laboratory of Solid-State Microstructures, Nanjing University, Nanjing 210093, China
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47
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Ogawa Y, Komatsu K, Kawahara K, Tsuji M, Tsukagoshi K, Ago H. Structure and transport properties of the interface between CVD-grown graphene domains. Nanoscale 2014; 6:7288-7294. [PMID: 24847777 DOI: 10.1039/c3nr06828e] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
During the chemical vapor deposition (CVD) growth of graphene, graphene domains grown on a Cu surface merge together and form a uniform graphene sheet. For high-performance electronics and other applications, it is important to understand the interfacial structure of the merged domains, as well as their influence on the physical properties of graphene. We synthesized large hexagonal graphene domains with controlled orientations on a heteroepitaxial Cu film and studied the structure and properties of the interfaces between the domains mainly merged with the same angle. Although the merged domains have various interfaces with/without wrinkles and/or increased defect-related Raman D-band intensity, the intra-domain transport showed higher carrier mobility reaching 20,000 cm(2) V(-1) s(-1) on SiO2 at 280 K (the mean value was 7200 cm(2) V(-1) s(-1)) than that measured for inter-domain areas, 6400 cm(2) V(-1) s(-1) (mean value 2000 cm(2) V(-1) s(-1)). The temperature dependence of the mobility suggests that impurity scattering dominates at the interface even for the merged domains with the same orientation. This study highlights the importance of domain interfaces, especially on the carrier transport properties, in CVD-grown graphene.
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Affiliation(s)
- Yui Ogawa
- Graduate School of Engineering Sciences, Kyushu University, Kasuga, Fukuoka 816-8580, Japan
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48
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Suda M, Kawasugi Y, Minari T, Tsukagoshi K, Kato R, Yamamoto HM. Strain-tunable superconducting field-effect transistor with an organic strongly-correlated electron system. Adv Mater 2014; 26:3490-3495. [PMID: 24664491 DOI: 10.1002/adma.201305797] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2013] [Revised: 01/31/2014] [Indexed: 06/03/2023]
Abstract
A novel type of flexible organic field-effect transistor in which strain effects can be finely tuned continuously has been fabricated. In this novel device structure, electronic phases can be controlled both by "band-filling" and by "band-width" continuously. Finally, co-regulation of "band-filling" and "band-width" in the strongly-correlated organic material realize field-induced emergence of superconducting fractions at low temperature.
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Affiliation(s)
- Masayuki Suda
- Research Center of Integrative Molecular Systems (CIMoS), Institute for Molecular Science, Okazaki, Aichi, 444-8585, Japan
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49
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Lin YF, Xu Y, Wang ST, Li SL, Yamamoto M, Aparecido-Ferreira A, Li W, Sun H, Nakaharai S, Jian WB, Ueno K, Tsukagoshi K. Ambipolar MoTe2 transistors and their applications in logic circuits. Adv Mater 2014; 26:3263-9. [PMID: 24692079 DOI: 10.1002/adma.201305845] [Citation(s) in RCA: 177] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 01/17/2014] [Indexed: 04/14/2023]
Abstract
We report ambipolar charge transport in α-molybdenum ditelluride (MoTe2 ) flakes, whereby the temperature dependence of the electrical characteristics was systematically analyzed. The ambipolarity of the charge transport originated from the formation of Schottky barriers at the metal/MoTe2 contacts. The Schottky barrier heights as well as the current on/off ratio could be modified by modulating the electrostatic fields of the back-gate voltage (Vbg) and drain-source voltage (Vds). Using these ambipolar MoTe2 transistors we fabricated complementary inverters and amplifiers, demonstrating their feasibility for future digital and analog circuit applications.
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Affiliation(s)
- Yen-Fu Lin
- WPI Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, 305-0044, Japan; Department of Physics, National Chung-Hsing University, Taichung, 40227, Taiwan
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50
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Yamamoto M, Wang ST, Ni M, Lin YF, Li SL, Aikawa S, Jian WB, Ueno K, Wakabayashi K, Tsukagoshi K. Strong enhancement of Raman scattering from a bulk-inactive vibrational mode in few-layer MoTe₂. ACS Nano 2014; 8:3895-3903. [PMID: 24654654 DOI: 10.1021/nn5007607] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Two-dimensional layered crystals could show phonon properties that are markedly distinct from those of their bulk counterparts, because of the loss of periodicities along the c-axis directions. Here we investigate the phonon properties of bulk and atomically thin α-MoTe2 using Raman spectroscopy. The Raman spectrum of α-MoTe2 shows a prominent peak of the in-plane E(1)2g mode, with its frequency upshifting with decreasing thickness down to the atomic scale, similar to other dichalcogenides. Furthermore, we find large enhancement of the Raman scattering from the out-of-plane B(1)2g mode in the atomically thin layers. The B(1)2g mode is Raman inactive in the bulk, but is observed to become active in the few-layer films. The intensity ratio of the B(1)2g to E(1)2g peaks evolves significantly with decreasing thickness, in contrast with other dichalcogenides. Our observations point to strong effects of dimensionality on the phonon properties of MoTe2.
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Affiliation(s)
- Mahito Yamamoto
- International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS) , Tsukuba, Ibaraki 305-0044, Japan
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