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Li Z, Bretscher H, Rao A. Chemical passivation of 2D transition metal dichalcogenides: strategies, mechanisms, and prospects for optoelectronic applications. NANOSCALE 2024; 16:9728-9741. [PMID: 38700268 DOI: 10.1039/d3nr06296a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
The interest in obtaining high-quality monolayer transition metal dichalcogenides (TMDs) for optoelectronic device applications has been growing dramatically. However, the prevalence of defects and unwanted doping in these materials remain challenges, as they both limit optical properties and device performance. Surface chemical treatments of monolayer TMDs have been effective in improving their photoluminescence yield and charge transport properties. In this scenario, a systematic understanding of the underlying mechanism of chemical treatments will lead to a rational design of passivation strategies in future research, ultimately taking a step toward practical optoelectronic applications. We will therefore describe in this mini-review the strategies, progress, mechanisms, and prospects of chemical treatments to passivate and improve the optoelectronic properties of TMDs.
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Affiliation(s)
- Zhaojun Li
- Solid State Physics, Department of Materials Science and Engineering, Uppsala University, 75103 Uppsala, Sweden.
| | - Hope Bretscher
- The Max Planck Institute for the Structure and Dynamics of Matter, 22761, Hamburg, Germany
| | - Akshay Rao
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, UK
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2
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Chen Y, Liu H, Yu G, Ma C, Xu Z, Zhang J, Zhang C, Chen M, Li D, Zheng W, Luo Z, Yang X, Li K, Yao C, Zhang D, Xu B, Yi J, Yi C, Li B, Zhang H, Zhang Z, Zhu X, Li S, Chen S, Jiang Y, Pan A. Defect Engineering of 2D Semiconductors for Dual Control of Emission and Carrier Polarity. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2312425. [PMID: 38146671 DOI: 10.1002/adma.202312425] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/10/2023] [Indexed: 12/27/2023]
Abstract
2D transition metal dichalcogenides (TMDCs) are considered as promising materials in post-Moore technology. However, the low photoluminescence quantum yields (PLQY) and single carrier polarity due to the inevitable defects during material preparation are great obstacles to their practical applications. Here, an extraordinary defect engineering strategy is reported based on first-principles calculations and realize it experimentally on WS2 monolayers by doping with IIIA atoms. The doped samples with large sizes possess both giant PLQY enhancement and effective carrier polarity modulation. Surprisingly, the high PL emission maintained even after one year under ambient environment. Moreover, the constructed p-n homojunctions shows high rectification ratio (≈2200), ultrafast response times and excellent stability. Meanwhile, the doping strategy is universally applicable to other TMDCs and dopants. This smart defect engineering strategy not only provides a general scheme to eliminate the negative influence of defects, but also utilize them to achieve desired optoelectronic properties for multifunctional applications.
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Affiliation(s)
- Ying Chen
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Huawei Liu
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Guoliang Yu
- School of Physics and Electronics, Hunan Normal University, Changsha, Hunan, 410081, China
| | - Chao Ma
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Zheyuan Xu
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Jinding Zhang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Cheng Zhang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Mingxing Chen
- School of Physics and Electronics, Hunan Normal University, Changsha, Hunan, 410081, China
| | - Dong Li
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Weihao Zheng
- College of Advanced Interdisciplinary Studies & Hunan Provincial Key Laboratory of Novel Nano Optoelectronic Information Materials and Devices, National University of Defense Technology, Changsha, Hunan, 410073, China
| | - Ziyu Luo
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Xin Yang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Kaihui Li
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Chengdong Yao
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Danliang Zhang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Boyi Xu
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Jiali Yi
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Chen Yi
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Bo Li
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Hongmei Zhang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Zucheng Zhang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Xiaoli Zhu
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Siyu Li
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Shula Chen
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Ying Jiang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
| | - Anlian Pan
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, School of Physics and Electronics, Hunan University, Changsha, Hunan, 410082, P. R. China
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Wang Y, Han B, Mayor M, Samorì P. Opto-Electrochemical Synaptic Memory in Supramolecularly Engineered Janus 2D MoS 2. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2307359. [PMID: 37903551 DOI: 10.1002/adma.202307359] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 10/25/2023] [Indexed: 11/01/2023]
Abstract
Artificial synapses combining multiple yet independent signal processing strategies in a single device are key enabler to achieve high-density of integration, energy efficiency, and fast data manipulation in brain-like computing. By taming functional complexity, the use of hybrids comprising multiple materials as active components in synaptic devices represents a powerful route to encode both short-term potentiation (STP) and long-term potentiation (LTP) in synaptic circuitries. To meet such a grand challenge, herein a novel Janus 2D material is developed by dressing asymmetrically the two surfaces of 2D molybdenum disulfide (MoS2 ) with an electrochemically-switchable ferrocene (Fc)/ ferrocenium (Fc+ ) redox couple and an optically-responsive photochromic azobenzene (Azo). Upon varying the magnitude of the electrochemical stimulus, it is possible to steer the transition between STP and LTP, thereby either triggering electrochemical doping of Fc/Fc+ pair on MoS2 or controlling an adsorption/desorption process of such redox species on MoS2 . In addition, a lower magnitude LTP is recorded by activating the photoisomerization of azobenzene chemisorbed molecules and therefore modulating the dipole-induced doping of the 2D semiconductor. Significantly, the interplay of electrochemical and optical stimuli makes it possible to construct artificial synapses where LTP can be boosted to 4-bit (16 memory states) while simultaneously functioning as STP.
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Affiliation(s)
- Ye Wang
- University of Strasbourg, CNRS, ISIS UMR 7006, 8 Alleé Gaspard Monge, Strasbourg, F-67000, France
| | - Bin Han
- University of Strasbourg, CNRS, ISIS UMR 7006, 8 Alleé Gaspard Monge, Strasbourg, F-67000, France
| | - Marcel Mayor
- Department of Chemistry, University of Basel, St. Johannsring 19, Basel, 4056, Switzerland
- Karlsruhe Institute of Technology KIT, Institute for Nanotechnology, P.O. Box 3640, 76021, Karlsruhe, Germany
| | - Paolo Samorì
- University of Strasbourg, CNRS, ISIS UMR 7006, 8 Alleé Gaspard Monge, Strasbourg, F-67000, France
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Ahn B, Kim Y, Kim M, Yu HM, Ahn J, Sim E, Ji H, Gul HZ, Kim KS, Ihm K, Lee H, Kim EK, Lim SC. One-Step Passivation of Both Sulfur Vacancies and SiO 2 Interface Traps of MoS 2 Device. NANO LETTERS 2023; 23:7927-7933. [PMID: 37647420 DOI: 10.1021/acs.nanolett.3c01753] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Transition metal dichalcogenides (TMDs) benefit electrical devices with spin-orbit coupling and valley- and topology-related properties. However, TMD-based devices suffer from traps arising from defect sites inside the channel and the gate oxide interface. Deactivating them requires independent treatments, because the origins are dissimilar. This study introduces a single treatment to passivate defects in a multilayer MoS2 FET. By applying back-gate bias, protons from an H-TFSI droplet are injected into the MoS2, penetrating deeply enough to reach the SiO2 gate oxide. The characterizations employing low-temperature transport and deep-level transient spectroscopy (DLTS) studies reveal that the trap density of S vacancies in MoS2 drops to the lowest detection level. The temperature-dependent mobility plot on the SiO2 substrate resembles that of the h-BN substrate, implying that dangling bonds in SiO2 are passivated. The carrier mobility on the SiO2 substrate is enhanced by approximately 2200% after the injection.
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Affiliation(s)
- Byungwook Ahn
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Yoonsok Kim
- Department of Physics, Hanyang University, Seoul 04763, Republic of Korea
- Institute of Plasma Technology, Korea Institute of Fusion Energy, Gunsan 54004, Republic of Korea
| | - Meeree Kim
- Department of Chemistry, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Hyang Mi Yu
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Jaehun Ahn
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Eunji Sim
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Hyunjin Ji
- Department of Electrical Engineering, University of Ulsan, Ulsan 44610, Republic of Korea
| | - Hamza Zad Gul
- Department of Electrical Engineering, Namal University, 30 km Talagang Road, Mianwali 42250, Pakistan
| | - Keun Soo Kim
- Department of Physics and Graphene Research Institute, Sejong University, Seoul 05006, Republic of Korea
| | - Kyuwook Ihm
- Nano & Interface Research Team, Pohang Accelerator Laboratory, Pohang 37673, Republic of Korea
| | - Hyoyoung Lee
- Department of Chemistry, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Eun Kyu Kim
- Department of Physics, Hanyang University, Seoul 04763, Republic of Korea
| | - Seong Chu Lim
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
- Department of Smart Fabrication Technology, Sungkyunkwan University, Suwon 16419, Republic of Korea
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5
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Kiriya D, Lien DH. Superacid Treatment on Transition Metal Dichalcogenides. NANO EXPRESS 2022. [DOI: 10.1088/2632-959x/ac87c2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
Superacids are strong acids with an acidity higher than pure sulfuric acid. Recently, superacid treatment of monolayer transition metal dichalcogenide (TMDC) flakes, such as MoS2 and WS2, has shown a dramatic enhancement of optical properties, such as photoluminescence (PL) intensity. The superacid molecule is bis(trifluoromethane)sulfonimide (TFSI). In this review paper, we summarize and discuss the recent works and the current understanding of the TFSI treatment, and finally, we describe the outlook of the treatment on monolayer TMDCs.
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Wells RA, Zhang M, Chen TH, Boureau V, Caretti M, Liu Y, Yum JH, Johnson H, Kinge S, Radenovic A, Sivula K. High Performance Semiconducting Nanosheets via a Scalable Powder-Based Electrochemical Exfoliation Technique. ACS NANO 2022; 16:5719-5730. [PMID: 35290010 DOI: 10.1021/acsnano.1c10739] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The liquid-phase exfoliation of semiconducting transition metal dichalcogenide (TMD) powders into 2D nanosheets represents a promising route toward the scalable production of ultrathin high-performance optoelectronic devices. However, the harsh conditions required negatively affect the semiconducting properties, leading to poor device performance. Herein we demonstrate a gentle exfoliation method employing standard bulk MoS2 powder (pressed into pellets) together with the electrochemical intercalation of a quaternary alkyl ammonium. The resulting nanosheets are produced in high yield (32%) and consist primarily of mono-, bi-, triatomic layers with large lateral dimensions (>1 μm), while retaining the semiconducting polymorph. Exceptional optoelectronic performance of nanosheet thin-films is observed, such as enhanced photoluminescence, charge carrier mobility (up to 0.2 cm2 V-1 s-1 in a multisheet device), and photon-to-current efficiency while maintaining high transparency (>80%). Specifically, as a photoanode for iodide oxidation, an internal quantum efficiency up to 90% (at +0.3 V vs Pt) is achieved (compared to only 12% for MoS2 nanosheets produced via ultrasonication). Further using a combination of fluorescence microscopy and high-resolution scanning transmission electron microscopy (STEM), we show that our gently exfoliated nanosheets possess a defect density (2.33 × 1013 cm-2) comparable to monolayer MoS2 prepared by vacuum-based techniques and at least three times less than ultrasonicated MoS2 nanoflakes. Finally, we expand this method toward other TMDs (WS2, WSe2) to demonstrate its versatility toward high-performance and fully scalable van der Waals heterojunction devices.
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Affiliation(s)
- Rebekah A Wells
- Laboratory for Molecular Engineering of Optoelectronic Nanomaterials (LIMNO), Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Miao Zhang
- Laboratory of Nanoscale Biology (LBEN), Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Tzu-Heng Chen
- Laboratory of Nanoscale Biology (LBEN), Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Victor Boureau
- Interdisciplinary Center for Electron Microscopy (CIME), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Marina Caretti
- Laboratory for Molecular Engineering of Optoelectronic Nanomaterials (LIMNO), Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Yongpeng Liu
- Laboratory for Molecular Engineering of Optoelectronic Nanomaterials (LIMNO), Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Jun-Ho Yum
- Laboratory for Molecular Engineering of Optoelectronic Nanomaterials (LIMNO), Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Hannah Johnson
- Laboratory for Molecular Engineering of Optoelectronic Nanomaterials (LIMNO), Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
- Advanced Materials Research, Toyota Motor Europe, B-1930 Zaventem, Belgium
| | - Sachin Kinge
- Advanced Materials Research, Toyota Motor Europe, B-1930 Zaventem, Belgium
| | - Aleksandra Radenovic
- Laboratory of Nanoscale Biology (LBEN), Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Kevin Sivula
- Laboratory for Molecular Engineering of Optoelectronic Nanomaterials (LIMNO), Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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Huang L, Krasnok A, Alú A, Yu Y, Neshev D, Miroshnichenko AE. Enhanced light-matter interaction in two-dimensional transition metal dichalcogenides. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2022; 85:046401. [PMID: 34939940 DOI: 10.1088/1361-6633/ac45f9] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 12/16/2021] [Indexed: 05/27/2023]
Abstract
Two-dimensional (2D) transition metal dichalcogenide (TMDC) materials, such as MoS2, WS2, MoSe2, and WSe2, have received extensive attention in the past decade due to their extraordinary electronic, optical and thermal properties. They evolve from indirect bandgap semiconductors to direct bandgap semiconductors while their layer number is reduced from a few layers to a monolayer limit. Consequently, there is strong photoluminescence in a monolayer (1L) TMDC due to the large quantum yield. Moreover, such monolayer semiconductors have two other exciting properties: large binding energy of excitons and valley polarization. These properties make them become ideal materials for various electronic, photonic and optoelectronic devices. However, their performance is limited by the relatively weak light-matter interactions due to their atomically thin form factor. Resonant nanophotonic structures provide a viable way to address this issue and enhance light-matter interactions in 2D TMDCs. Here, we provide an overview of this research area, showcasing relevant applications, including exotic light emission, absorption and scattering features. We start by overviewing the concept of excitons in 1L-TMDC and the fundamental theory of cavity-enhanced emission, followed by a discussion on the recent progress of enhanced light emission, strong coupling and valleytronics. The atomically thin nature of 1L-TMDC enables a broad range of ways to tune its electric and optical properties. Thus, we continue by reviewing advances in TMDC-based tunable photonic devices. Next, we survey the recent progress in enhanced light absorption over narrow and broad bandwidths using 1L or few-layer TMDCs, and their applications for photovoltaics and photodetectors. We also review recent efforts of engineering light scattering, e.g., inducing Fano resonances, wavefront engineering in 1L or few-layer TMDCs by either integrating resonant structures, such as plasmonic/Mie resonant metasurfaces, or directly patterning monolayer/few layers TMDCs. We then overview the intriguing physical properties of different van der Waals heterostructures, and their applications in optoelectronic and photonic devices. Finally, we draw our opinion on potential opportunities and challenges in this rapidly developing field of research.
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Affiliation(s)
- Lujun Huang
- School of Engineering and Information Technology, University of New South Wales, Canberra, ACT, 2600, Australia
| | - Alex Krasnok
- Department of Electrical and Computer Engineering, Florida International University, Miami, FL 33174, United States of America
| | - Andrea Alú
- Photonics Initiative, Advanced Science Research Center, City University of New York, New York, NY 10031, United States of America
- Physics Program, Graduate Center, City University of New York, New York, NY 10016, United States of America
| | - Yiling Yu
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States of America
| | - Dragomir Neshev
- ARC Centre of Excellence for Transformative Meta-Optical Systems (TMOS), Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, ACT 2601, Australia
| | - Andrey E Miroshnichenko
- School of Engineering and Information Technology, University of New South Wales, Canberra, ACT, 2600, Australia
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Liu M, Ma L, Xie K, Zeng P, Wei S, Zhang F, Li C, Wang F. Efficiently Improved Photoluminescence in Cesium Lead Halide Perovskite Nanocrystals by Using Bis(trifluoromethane)sulfonimide. J Phys Chem Lett 2022; 13:1519-1525. [PMID: 35133165 DOI: 10.1021/acs.jpclett.2c00010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Cesium lead halide perovskite (CsPbX3, X = Cl, Br, and I) nanocrystals (NCs) have attracted enormous attention because of their great potential for optoelectronic applications, such as light-emitting diodes (LEDs). However, the photoluminescence and surface ligands of CsPbX3 NCs have a great impact on their device applications. Herein, we report a molecular superacid of bis(trifluoromethane)sulfonimide (TFSI), which could boost the photoluminescence in the metal halide perovskite nanocrystals. In particular, the photoluminescence quantum yield (PLQY) of CsPbI3 nanocrystals could be greatly improved from 28.6% to near 100% with the superacid treatment. The improved PLQY in CsPbX3 nanocrystals is mainly contributed from the surface passivation based on the characterizations. The CsPbX3 nanocrystals were further modified with PMMA, which could greatly improve their stability while preserving high photoluminescence and good dispersion. The use of superacid combined with a polymer for improving the photoluminescence and stability in CsPbX3 provides an alternative strategy for optoelectronics.
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Affiliation(s)
- Mengyuan Liu
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng 475004, P.R. China
| | - Le Ma
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng 475004, P.R. China
| | - Kehan Xie
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng 475004, P.R. China
| | - Piaopiao Zeng
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng 475004, P.R. China
| | - Shijing Wei
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng 475004, P.R. China
| | - Feng Zhang
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng 475004, P.R. China
| | - Chao Li
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng 475004, P.R. China
| | - Feijiu Wang
- Henan Key Laboratory of Photovoltaic Materials, Henan University, 1 Jinming Road, Kaifeng 475004, P.R. China
- Center for Topological Functional Materials, Henan University, 1 Jinming Road, Kaifeng 475004, P.R. China
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9
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Pain SL, Grant NE, Murphy JD. Room Temperature Enhancement of Electronic Materials by Superacid Analogues. ACS NANO 2022; 16:1260-1270. [PMID: 34978794 DOI: 10.1021/acsnano.1c09085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Treatment with the superacid bis(trifluoromethanesulfonyl)amide (sometimes known as TFSA, TFSI, or HNTf2) enhances the properties of a wide range of optoelectronic materials, resulting in longer effective carrier lifetimes and higher photoluminescence quantum yields. We have conducted a multimaterial study treating both crystalline silicon and transition metal dichalcogenide (TMDC) monolayers and few-layer flakes with solutions formed from TFSA and a range of compounds with related chemical structures with different Lewis acidities, in order to elucidate the factors underpinning the TFSA-related class of enhancement treatments. We adopt dichloromethane (DCM) as a common solvent as it provides good results at room temperature and is potentially less hazardous than TFSA-dichloroethane (DCE) heated to ∼100 °C, which has been used previously. Kelvin probe experiments on silicon demonstrate that structurally similar chemicals give passivating films with substantially different charge levels, with the higher levels of charge associated with the presence of CF3SO2 groups resulting in longer effective lifetimes due to an enhancement in field-effect passivation. Treatment with all analogue solutions used results in enhanced photoluminescence in MoS2 and WS2 compared to untreated controls. Importantly we find that MoS2 and WS2 can be enhanced by analogues to TFSA that lack sulfonyl groups, meaning an alternative mechanism to that proposed in computational reports for TFSA enhancement must apply.
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Affiliation(s)
- Sophie L Pain
- School of Engineering, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Nicholas E Grant
- School of Engineering, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - John D Murphy
- School of Engineering, University of Warwick, Coventry CV4 7AL, United Kingdom
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Nguyen DK, Guerrero-Sanchez J, Van On V, Rivas-Silva JF, Ponce-Pérez R, Cocoletzi GH, Hoat DM. Tuning MoSO monolayer properties for optoelectronic and spintronic applications: effect of external strain, vacancies and doping. RSC Adv 2021; 11:35614-35623. [PMID: 35493147 PMCID: PMC9043256 DOI: 10.1039/d1ra05639e] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 10/29/2021] [Indexed: 12/02/2022] Open
Abstract
Since the successful synthesis of the MoSSe monolayer, two-dimensional (2D) Janus materials have attracted huge attention from researchers. In this work, the MoSO monolayer with tunable electronic and magnetic properties is comprehensively investigated using first-principles calculations based on density functional theory (DFT). The pristine MoSO single layer is an indirect gap semiconductor with energy gap of 1.02(1.64) eV as predicted by the PBE(HSE06) functional. This gap feature can be efficiently modified by applying external strain presenting a decrease in its value upon switching the strain from compressive to tensile. In addition, the effects of vacancies and doping at Mo, S, and O sites on the electronic structure and magnetic properties are examined. Results reveal that Mo vacancies, and Al and Ga doping yield magnetic semiconductor 2D materials, where both spin states are semiconductors with significant spin-polarization at the vicinity of the Fermi level. In contrast, single S and O vacancies induce a considerable gap reduction of 52.89% and 58.78%, respectively. Doping the MoSO single layer with F and Cl at both S and O sites will form half-metallic 2D materials, whose band structures are generated by a metallic spin-up state and direct gap semiconductor spin-down state. Consequently, MoV, MoAl, MoGa, SF, SCl, OF, and OCl are magnetic systems, and the magnetism is produced mainly by the Mo transition metal that exhibits either ferromagnetic or antiferromagnetic coupling. Our work may suggest the MoSO Janus monolayer as a prospective candidate for optoelectronic applications, as well as proposing an efficient approach to functionalize it to be employed in optoelectronic and spintronic devices. Atomic structure and stability analysis of the MoSO Janus monolayer.![]()
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Affiliation(s)
- Duy Khanh Nguyen
- Group of Computational Physics and Simulation of Advanced Materials, Institute of Applied Technology, Thu Dau Mot University Binh Duong Province Vietnam
| | - J Guerrero-Sanchez
- Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología Apartado Postal 14 Ensenada Baja California Código Postal 22800 Mexico
| | - Vo Van On
- Group of Computational Physics and Simulation of Advanced Materials, Institute of Applied Technology, Thu Dau Mot University Binh Duong Province Vietnam
| | - J F Rivas-Silva
- Benemérita Universidad Autónoma de Puebla, Instituto de Física Apartado Postal J-48 Puebla 72570 Mexico
| | - R Ponce-Pérez
- Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología Apartado Postal 14 Ensenada Baja California Código Postal 22800 Mexico
| | - Gregorio H Cocoletzi
- Benemérita Universidad Autónoma de Puebla, Instituto de Física Apartado Postal J-48 Puebla 72570 Mexico
| | - D M Hoat
- Institute of Theoretical and Applied Research, Duy Tan University Hanoi 100000 Vietnam .,Faculty of Natural Sciences, Duy Tan University Da Nang 550000 Vietnam
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11
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Tanoh AOA, Alexander-Webber J, Fan Y, Gauriot N, Xiao J, Pandya R, Li Z, Hofmann S, Rao A. Giant photoluminescence enhancement in MoSe 2 monolayers treated with oleic acid ligands. NANOSCALE ADVANCES 2021; 3:4216-4225. [PMID: 34355119 PMCID: PMC8276785 DOI: 10.1039/d0na01014f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 06/09/2021] [Indexed: 05/28/2023]
Abstract
The inherently low photoluminescence (PL) yields in the as prepared transition metal dichalcogenide (TMD) monolayers are broadly accepted to be the result of atomic vacancies (i.e., defects) and uncontrolled doping, which give rise to non-radiative exciton decay pathways. To date, a number of chemical passivation schemes have been successfully developed to improve PL in sulphur based TMDs i.e., molybdenum disulphide (MoS2) and tungsten disulphide (WS2) monolayers. Studies on solution based chemical passivation schemes for improving PL yields in selenium (Se) based TMDs are however lacking in comparison. Here, we demonstrate that treatment with oleic acid (OA) provides a simple wet chemical passivation method for monolayer MoSe2, enhancing PL yields by an average of 58-fold, while also improving spectral uniformity across the material and reducing the emission linewidth. Excitation intensity dependent PL reveals trap-free PL dynamics dominated by neutral exciton recombination. Time-resolved PL (TRPL) studies reveal significantly increased PL lifetimes, with pump intensity dependent TRPL measurements also confirming trap free PL dynamics in OA treated MoSe2. Field effect transistors show reduced charge trap density and improved on-off ratios after treatment with OA. These results indicate defect passivation by OA, which we hypothesise as ligands passivating chalcogen defects through oleate coordination to Mo dangling bonds. Importantly, this work combined with our previous study on OA treated WS2, verifies OA treatment as a simple solution-based chemical passivation protocol for improving PL yields and electronic characteristics in both selenide and sulphide TMDs - a property that has not been reported previously for other solution-based passivation schemes.
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Affiliation(s)
- Arelo O A Tanoh
- Cavendish Laboratory, Cambridge JJ Thomson Avenue CB3 0HE Cambridge UK
- Cambridge Graphene Centre, University of Cambridge 9 JJ Thomson Avenue CB3 0FA Cambridge UK
| | - Jack Alexander-Webber
- Department of Engineering, University of Cambridge JJ Thomson Avenue CB3 0FA Cambridge UK
| | - Ye Fan
- Department of Engineering, University of Cambridge JJ Thomson Avenue CB3 0FA Cambridge UK
| | - Nicholas Gauriot
- Cavendish Laboratory, Cambridge JJ Thomson Avenue CB3 0HE Cambridge UK
| | - James Xiao
- Cavendish Laboratory, Cambridge JJ Thomson Avenue CB3 0HE Cambridge UK
| | - Raj Pandya
- Cavendish Laboratory, Cambridge JJ Thomson Avenue CB3 0HE Cambridge UK
| | - Zhaojun Li
- Cavendish Laboratory, Cambridge JJ Thomson Avenue CB3 0HE Cambridge UK
| | - Stephan Hofmann
- Department of Engineering, University of Cambridge JJ Thomson Avenue CB3 0FA Cambridge UK
| | - Akshay Rao
- Cavendish Laboratory, Cambridge JJ Thomson Avenue CB3 0HE Cambridge UK
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12
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Yamada Y, Zhang Y, Ikeno H, Shinokita K, Yoshimura T, Ashida A, Fujimura N, Matsuda K, Kiriya D. Ultralarge Photoluminescence Enhancement of Monolayer Molybdenum Disulfide by Spontaneous Superacid Nanolayer Formation. ACS APPLIED MATERIALS & INTERFACES 2021; 13:25280-25289. [PMID: 34011141 DOI: 10.1021/acsami.1c04980] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Due to the direct band gap nature, extensive studies have been conducted to improve the optical behavior in monolayer transition metal dichalcogenides (TMDCs) with a formula of MX2 (M = Mo, W; X = S, Se, Te). One of the strongest modulating agents of optical behavior is a molecular superacid treatment; however, the chemical event has not been unveiled. Also, the engineering protocol for keeping the treatment is immature. In this work, we systematically study the superacid treatment procedures on monolayer molybdenum disulfide (MoS2) and propose that the interaction, a hydrophilic interaction, between the superacid molecule and MoS2 surface would be critical. As a result of the interaction, the superacid molecules spontaneously form an acidic layer with the thickness of several nanometers on the surface. The power-dependent photoluminescence (PL) measurement indicates the edge of MoS2 flake is more effective and electronically modulated by the treatment. By understanding the superacid nanolayer formation by the treatment, we succeeded in maintaining the ultrastrong PL in the superacid-treated MoS2 for more than 30 days in the ambient air by encapsulation with transparent organic polymers. This study advances the understanding and designing applications of strong luminescent properties in the superacid-treated TMDCs and paves the way toward engineering exciton dynamics and an experimental platform for treating multibody states.
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Affiliation(s)
- Yuki Yamada
- Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka 599-8531, Japan
| | - Yan Zhang
- Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Hidekazu Ikeno
- Department of Materials Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka 599-8531, Japan
| | - Keisuke Shinokita
- Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Takeshi Yoshimura
- Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka 599-8531, Japan
| | - Atsushi Ashida
- Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka 599-8531, Japan
| | - Norifumi Fujimura
- Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka 599-8531, Japan
| | - Kazunari Matsuda
- Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Daisuke Kiriya
- Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka 599-8531, Japan
- PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Saitama Japan
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13
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Yue YY, Wang Z, Wang L, Wang HY, Chen Y, Wang D, Chen QD, Gao BR, Wee ATS, Qiu CW, Sun HB. Many-particle induced band renormalization processes in few- and mono-layer MoS 2. NANOTECHNOLOGY 2021; 32:135208. [PMID: 33427201 DOI: 10.1088/1361-6528/abcfec] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 12/02/2020] [Indexed: 06/12/2023]
Abstract
Band renormalization effects play a significant role for two-dimensional (2D) materials in designing a device structure and customizing their optoelectronic performance. However, the intrinsic physical mechanism about the influence of these effects cannot be revealed by general steady-state studies. Here, band renormalization effects in organic superacid treated monolayer MoS2, untreated monolayer MoS2and few-layer MoS2are quantitatively analyzed by using broadband femtosecond transient absorption spectroscopy. In comparison with the untreated monolayer, organic superacid treated monolayer MoS2maintains a direct bandgap structure with two thirds of carriers populated at K valley, even when the initial exciton density is as high as 2.05 × 1014cm-2(under 400 nm excitations). While for untreated monolayer and few-layer MoS2, many-particle induced band renormalizations lead to a stronger imbalance for the carrier population between K and Q valleys inkspace, and the former experiences a direct-to-indirect bandgap transition when the initial exciton density exceeds 5.0 × 1013cm-2(under 400 nm excitations). Those many-particle induced band renormalization processes further suggest a band-structure-controlling method in practical 2D devices.
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Affiliation(s)
- Yuan-Yuan Yue
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, People's Republic of China
| | - Zhuo Wang
- International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, People's Republic of China
| | - Lei Wang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, People's Republic of China
- Department of Electrical & Computer Engineering, National University of Singapore, Singapore 117583, Singapore
| | - Hai-Yu Wang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, People's Republic of China
| | - Yang Chen
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, People's Republic of China
| | - Dan Wang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, People's Republic of China
| | - Qi-Dai Chen
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, People's Republic of China
| | - Bing-Rong Gao
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, People's Republic of China
| | - Andrew T S Wee
- Department of Physics, National University of Singapore, Singapore 117542, Singapore
| | - Cheng-Wei Qiu
- Department of Electrical & Computer Engineering, National University of Singapore, Singapore 117583, Singapore
| | - Hong-Bo Sun
- State Key Laboratory of Precision Measurement and Instruments, Department of Precision Instrument, Tsinghua University, Beijing 100084, People's Republic of China
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14
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Lv J, Cheng Y. Fluoropolymers in biomedical applications: state-of-the-art and future perspectives. Chem Soc Rev 2021; 50:5435-5467. [DOI: 10.1039/d0cs00258e] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Biomedical applications of fluoropolymers in gene delivery, protein delivery, drug delivery, 19F MRI, PDT, anti-fouling, anti-bacterial, cell culture, and tissue engineering.
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Affiliation(s)
- Jia Lv
- Shanghai Key Laboratory of Regulatory Biology
- School of Life Sciences
- East China Normal University
- Shanghai
- China
| | - Yiyun Cheng
- Shanghai Key Laboratory of Regulatory Biology
- School of Life Sciences
- East China Normal University
- Shanghai
- China
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15
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Vasquez RM, Hlynchuk S, Maldonado S. Effect of Covalent Surface Functionalization of Si on the Activity of Trifluoromethanesulfonic Anhydride for Suppressing Surface Recombination. ACS APPLIED MATERIALS & INTERFACES 2020; 12:57560-57568. [PMID: 33307671 DOI: 10.1021/acsami.0c16878] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
An examination of the efficacy of combining physisorbed and chemisorbed passivation strategies on crystalline Si has been performed. This report compares the influence of a linear alkyl adsorbate tethered by either a Si-C or Si-Si linkage, prepared by reaction of Si(111) with organometallic Grignard reagents or organosilanes, respectively. These modified surfaces are first analyzed and compared by IR and X-ray photoelectron spectroscopies. Their behavior toward a known potent physisorbate, trifluoromethanesulfonic anhydride (Tf2O), is then examined. Microwave photoconductivity measurements were obtained which indicate that, while Tf2O shows a beneficial lowering of surface recombination on both surface types initially, only surfaces featuring Si-C linkages exhibit long-lasting suppressed surface recombination. The data for Grignard-treated Si after exposure to Tf2O in fact represent the longest known report of surface recombination suppression by a physisorbate. Conversely, the data for the Si surfaces prepared by dehydrogenative coupling suggest that these passivating groups themselves introduce defect states that cannot be ameliorated by Tf2O physisorption.
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16
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Tanoh AOA, Gauriot N, Delport G, Xiao J, Pandya R, Sung J, Allardice J, Li Z, Williams CA, Baldwin A, Stranks SD, Rao A. Directed Energy Transfer from Monolayer WS 2 to Near-Infrared Emitting PbS-CdS Quantum Dots. ACS NANO 2020; 14:15374-15384. [PMID: 33078943 PMCID: PMC8155326 DOI: 10.1021/acsnano.0c05818] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 10/15/2020] [Indexed: 05/24/2023]
Abstract
Heterostructures of two-dimensional (2D) transition metal dichalcogenides (TMDs) and inorganic semiconducting zero-dimensional (0D) quantum dots (QDs) offer useful charge and energy transfer pathways, which could form the basis of future optoelectronic devices. To date, most have focused on charge transfer and energy transfer from QDs to TMDs, that is, from 0D to 2D. Here, we present a study of the energy transfer process from a 2D to 0D material, specifically exploring energy transfer from monolayer tungsten disulfide (WS2) to near-infrared emitting lead sulfide-cadmium sulfide (PbS-CdS) QDs. The high absorption cross section of WS2 in the visible region combined with the potentially high photoluminescence (PL) efficiency of PbS QD systems makes this an interesting donor-acceptor system that can effectively use the WS2 as an antenna and the QD as a tunable emitter, in this case, downshifting the emission energy over hundreds of millielectron volts. We study the energy transfer process using photoluminescence excitation and PL microscopy and show that 58% of the QD PL arises due to energy transfer from the WS2. Time-resolved photoluminescence microscopy studies show that the energy transfer process is faster than the intrinsic PL quenching by trap states in the WS2, thus allowing for efficient energy transfer. Our results establish that QDs could be used as tunable and high PL efficiency emitters to modify the emission properties of TMDs. Such TMD-QD heterostructures could have applications in light-emitting technologies or artificial light-harvesting systems or be used to read out the state of TMD devices optically in various logic and computing applications.
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Affiliation(s)
- Arelo O. A. Tanoh
- Cavendish Laboratory,
Cambridge, JJ Thomson
Avenue, Cambridge CB3 0HE, United Kingdom
- Cambridge Graphene Centre, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, United Kingdom
| | - Nicolas Gauriot
- Cavendish Laboratory,
Cambridge, JJ Thomson
Avenue, Cambridge CB3 0HE, United Kingdom
| | - Géraud Delport
- Cavendish Laboratory,
Cambridge, JJ Thomson
Avenue, Cambridge CB3 0HE, United Kingdom
| | - James Xiao
- Cavendish Laboratory,
Cambridge, JJ Thomson
Avenue, Cambridge CB3 0HE, United Kingdom
| | - Raj Pandya
- Cavendish Laboratory,
Cambridge, JJ Thomson
Avenue, Cambridge CB3 0HE, United Kingdom
| | - Jooyoung Sung
- Cavendish Laboratory,
Cambridge, JJ Thomson
Avenue, Cambridge CB3 0HE, United Kingdom
| | - Jesse Allardice
- Cavendish Laboratory,
Cambridge, JJ Thomson
Avenue, Cambridge CB3 0HE, United Kingdom
| | - Zhaojun Li
- Cavendish Laboratory,
Cambridge, JJ Thomson
Avenue, Cambridge CB3 0HE, United Kingdom
| | - Cyan A. Williams
- Cambridge Graphene Centre, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, United Kingdom
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United
Kingdom
| | - Alan Baldwin
- Cavendish Laboratory,
Cambridge, JJ Thomson
Avenue, Cambridge CB3 0HE, United Kingdom
| | - Samuel D. Stranks
- Cavendish Laboratory,
Cambridge, JJ Thomson
Avenue, Cambridge CB3 0HE, United Kingdom
- Department of Chemical Engineering & Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge CB3 0AS, United
Kingdom
| | - Akshay Rao
- Cavendish Laboratory,
Cambridge, JJ Thomson
Avenue, Cambridge CB3 0HE, United Kingdom
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17
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Yamada Y, Shinokita K, Okajima Y, Takeda SN, Matsushita Y, Takei K, Yoshimura T, Ashida A, Fujimura N, Matsuda K, Kiriya D. Photoactivation of Strong Photoluminescence in Superacid-Treated Monolayer Molybdenum Disulfide. ACS APPLIED MATERIALS & INTERFACES 2020; 12:36496-36504. [PMID: 32635713 DOI: 10.1021/acsami.0c09084] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
To advance the development of atomically thin optoelectronics using two-dimensional (2D) materials, engineering strong luminescence with a physicochemical basis is crucial. Semiconducting monolayer transition-metal dichalcogenides (TMDCs) are candidates for this, but their quantum yield (QY) is known to be poor. Recently, a molecular superacid treatment of bis(trifluoromethane)sulfonimide (TFSI) generated unambiguously bright monolayer TMDCs and a high QY. However, this method is highly dependent on the processing conditions and therefore has not been generalized. Here, we shed light on environmental factors to activate the photoluminescence (PL) intensity of the TFSI-treated monolayer MoS2, with a factor of more than 2 orders of magnitude greater than the original by photoactivation. The method is useful for both mechanically exfoliated and chemically deposited samples. The existence of photoirradiation larger than the band gap demonstrates enhancement of the PL of MoS2; on the other hand, activation by thermal annealing, as demonstrated in the previous report, is less effective for enhancing the PL intensity. The photoactivated monolayer MoS2 shows a long lifetime of ∼1.35 ns, more than a 30-fold improvement over the original as exfoliated. The consistent realization of the bright monolayer MoS2 reveals that air exposure is an essential factor in the process. TFSI treatment in a N2 environment was not effective for achieving a strong PL, even after the photoactivation. These findings can serve as a basis for engineering the bright atomically thin materials for 2D optoelectronics.
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Affiliation(s)
- Yuki Yamada
- Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka 599-8531, Japan
| | - Keisuke Shinokita
- Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Yasuo Okajima
- Graduate School of Materials Science, Nara Institute of Science and Technology (NAIST), 8916-5, Ikoma, Nara 630-0192, Japan
| | - Sakura N Takeda
- Graduate School of Materials Science, Nara Institute of Science and Technology (NAIST), 8916-5, Ikoma, Nara 630-0192, Japan
| | - Yuji Matsushita
- Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka 599-8531, Japan
| | - Kuniharu Takei
- Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka 599-8531, Japan
| | - Takeshi Yoshimura
- Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka 599-8531, Japan
| | - Atsushi Ashida
- Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka 599-8531, Japan
| | - Norifumi Fujimura
- Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka 599-8531, Japan
| | - Kazunari Matsuda
- Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Daisuke Kiriya
- Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai-shi, Osaka 599-8531, Japan
- PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
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18
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Tanoh AOA, Alexander-Webber J, Xiao J, Delport G, Williams CA, Bretscher H, Gauriot N, Allardice J, Pandya R, Fan Y, Li Z, Vignolini S, Stranks SD, Hofmann S, Rao A. Enhancing Photoluminescence and Mobilities in WS 2 Monolayers with Oleic Acid Ligands. NANO LETTERS 2019; 19:6299-6307. [PMID: 31419143 PMCID: PMC6746058 DOI: 10.1021/acs.nanolett.9b02431] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 07/26/2019] [Indexed: 05/28/2023]
Abstract
Many potential applications of monolayer transition metal dichalcogenides (TMDs) require both high photoluminescence (PL) yield and high electrical mobilities. However, the PL yield of as prepared TMD monolayers is low and believed to be limited by defect sites and uncontrolled doping. This has led to a large effort to develop chemical passivation methods to improve PL and mobilities. The most successful of these treatments is based on the nonoxidizing organic "superacid" bis(trifluoromethane)sulfonimide (TFSI) which has been shown to yield bright monolayers of molybdenum disulfide (MoS2) and tungsten disulfide (WS2) but with trap-limited PL dynamics and no significant improvements in field effect mobilities. Here, using steady-state and time-resolved PL microscopy we demonstrate that treatment of WS2 monolayers with oleic acid (OA) can greatly enhance the PL yield, resulting in bright neutral exciton emission comparable to TFSI treated monolayers. At high excitation densities, the OA treatment allows for bright trion emission, which has not been demonstrated with previous chemical treatments. We show that unlike the TFSI treatment, the OA yields PL dynamics that are largely trap free. In addition, field effect transistors show an increase in mobilities with the OA treatment. These results suggest that OA serves to passivate defect sites in the WS2 monolayers in a manner akin to the passivation of colloidal quantum dots with OA ligands. Our results open up a new pathway to passivate and tune defects in monolayer TMDs using simple "wet" chemistry techniques, allowing for trap-free electronic properties and bright neutral exciton and trion emission.
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Affiliation(s)
- Arelo O A Tanoh
- Cavendish Laboratory, Cambridge , JJ Thomson Avenue , CB3 0HE , Cambridge , United Kingdom
- Cambridge Graphene Centre , University of Cambridge , 9 JJ Thomson Avenue , Cambridge, CB3 0FA , Cambridge , United Kingdom
| | - Jack Alexander-Webber
- Department of Engineering , University of Cambridge , JJ Thomson Avenue , CB3 0FA Cambridge , United Kingdom
| | - James Xiao
- Cavendish Laboratory, Cambridge , JJ Thomson Avenue , CB3 0HE , Cambridge , United Kingdom
| | - Géraud Delport
- Cavendish Laboratory, Cambridge , JJ Thomson Avenue , CB3 0HE , Cambridge , United Kingdom
| | - Cyan A Williams
- Cambridge Graphene Centre , University of Cambridge , 9 JJ Thomson Avenue , Cambridge, CB3 0FA , Cambridge , United Kingdom
- Department of Chemistry , University of Cambridge , Lensfield Road , CB2 1EW , Cambridge , United Kingdom
| | - Hope Bretscher
- Cavendish Laboratory, Cambridge , JJ Thomson Avenue , CB3 0HE , Cambridge , United Kingdom
| | - Nicolas Gauriot
- Cavendish Laboratory, Cambridge , JJ Thomson Avenue , CB3 0HE , Cambridge , United Kingdom
| | - Jesse Allardice
- Cavendish Laboratory, Cambridge , JJ Thomson Avenue , CB3 0HE , Cambridge , United Kingdom
| | - Raj Pandya
- Cavendish Laboratory, Cambridge , JJ Thomson Avenue , CB3 0HE , Cambridge , United Kingdom
| | - Ye Fan
- Department of Engineering , University of Cambridge , JJ Thomson Avenue , CB3 0FA Cambridge , United Kingdom
| | - Zhaojun Li
- Cavendish Laboratory, Cambridge , JJ Thomson Avenue , CB3 0HE , Cambridge , United Kingdom
| | - Silvia Vignolini
- Department of Chemistry , University of Cambridge , Lensfield Road , CB2 1EW , Cambridge , United Kingdom
| | - Samuel D Stranks
- Cavendish Laboratory, Cambridge , JJ Thomson Avenue , CB3 0HE , Cambridge , United Kingdom
| | - Stephan Hofmann
- Department of Engineering , University of Cambridge , JJ Thomson Avenue , CB3 0FA Cambridge , United Kingdom
| | - Akshay Rao
- Cavendish Laboratory, Cambridge , JJ Thomson Avenue , CB3 0HE , Cambridge , United Kingdom
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19
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Sivaram SV, Hanbicki AT, Rosenberger MR, Jernigan GG, Chuang HJ, McCreary KM, Jonker BT. Spatially Selective Enhancement of Photoluminescence in MoS 2 by Exciton-Mediated Adsorption and Defect Passivation. ACS APPLIED MATERIALS & INTERFACES 2019; 11:16147-16155. [PMID: 30973218 DOI: 10.1021/acsami.9b00390] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Monolayers of transition-metal dichalcogenides (TMDs) are promising components for flexible optoelectronic devices because of their direct band gap and atomically thin nature. The photoluminescence (PL) from these materials is often strongly suppressed by nonradiative recombination mediated by midgap defect states. Here, we demonstrate up to a 200-fold increase in PL intensity from monolayer MoS2 synthesized by chemical vapor deposition (CVD) by controlled exposure to laser light in the ambient. This spatially resolved passivation treatment is stable in air and vacuum. Regions unexposed to laser light remain dark in fluorescence despite continuous impingement of ambient gas molecules. A wavelength-dependent study confirms that PL brightening is concomitant with exciton generation in the MoS2; laser light below the optical band gap fails to produce any enhancement in the PL. We highlight the photosensitive nature of the process by successfully brightening with a low-power broadband white light source. We decouple changes in absorption from defect passivation by examining the degree of circularly polarized PL. This measurement, which is independent of exciton generation, confirms that laser brightening reduces the rate of nonradiative recombination in the MoS2. A series of gas exposure studies demonstrate a clear correlation between PL brightening and the presence of water. We propose that H2O molecules passivate sulfur vacancies in the CVD-grown MoS2 but require photogenerated excitons to overcome a large adsorption barrier. This work represents an important step in understanding the passivation of CVD-synthesized TMDs and demonstrates the interplay between adsorption and exciton generation.
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20
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Singh E, Singh P, Kim KS, Yeom GY, Nalwa HS. Flexible Molybdenum Disulfide (MoS 2) Atomic Layers for Wearable Electronics and Optoelectronics. ACS APPLIED MATERIALS & INTERFACES 2019; 11:11061-11105. [PMID: 30830744 DOI: 10.1021/acsami.8b19859] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Flexible, stretchable, and bendable materials, including inorganic semiconductors, organic polymers, graphene, and transition metal dichalcogenides (TMDs), are attracting great attention in such areas as wearable electronics, biomedical technologies, foldable displays, and wearable point-of-care biosensors for healthcare. Among a broad range of layered TMDs, atomically thin layered molybdenum disulfide (MoS2) has been of particular interest, due to its exceptional electronic properties, including tunable bandgap and charge carrier mobility. MoS2 atomic layers can be used as a channel or a gate dielectric for fabricating atomically thin field-effect transistors (FETs) for electronic and optoelectronic devices. This review briefly introduces the processing and spectroscopic characterization of large-area MoS2 atomically thin layers. The review summarizes the different strategies in enhancing the charge carrier mobility and switching speed of MoS2 FETs by integrating high-κ dielectrics, encapsulating layers, and other 2D van der Waals layered materials into flexible MoS2 device structures. The photoluminescence (PL) of MoS2 atomic layers has, after chemical treatment, been dramatically improved to near-unity quantum yield. Ultraflexible and wearable active-matrix organic light-emitting diode (AM-OLED) displays and wafer-scale flexible resistive random-access memory (RRAM) arrays have been assembled using flexible MoS2 transistors. The review discusses the overall recent progress made in developing MoS2 based flexible FETs, OLED displays, nonvolatile memory (NVM) devices, piezoelectric nanogenerators (PNGs), and sensors for wearable electronic and optoelectronic devices. Finally, it outlines the perspectives and tremendous opportunities offered by a large family of atomically thin-layered TMDs.
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Affiliation(s)
- Eric Singh
- Department of Computer Science , Stanford University , Stanford , California 94305 , United States
| | - Pragya Singh
- Department of Electrical Engineering and Computer Science , National Chiao Tung University , Hsinchu 30010 , Taiwan , R.O.C
| | - Ki Seok Kim
- School of Advanced Materials Science and Engineering , Sungkyunkwan University , 2066 Seobu-ro, Jangan-gu , Suwon-si , Gyeonggi-do 16419 , South Korea
| | - Geun Young Yeom
- School of Advanced Materials Science and Engineering , Sungkyunkwan University , 2066 Seobu-ro, Jangan-gu , Suwon-si , Gyeonggi-do 16419 , South Korea
- SKKU Advanced Institute of Nano Technology , Sungkyunkwan University , 2066 Seobu-ro, Jangan-gu , Suwon-si , Gyeonggi-do 16419 , South Korea
| | - Hari Singh Nalwa
- Advanced Technology Research , 26650 The Old Road, Suite 208 , Valencia , California 91381 , United States
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21
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Jakubczyk T, Nayak G, Scarpelli L, Liu WL, Dubey S, Bendiab N, Marty L, Taniguchi T, Watanabe K, Masia F, Nogues G, Coraux J, Langbein W, Renard J, Bouchiat V, Kasprzak J. Coherence and Density Dynamics of Excitons in a Single-Layer MoS 2 Reaching the Homogeneous Limit. ACS NANO 2019; 13:3500-3511. [PMID: 30735350 PMCID: PMC6527262 DOI: 10.1021/acsnano.8b09732] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 02/08/2019] [Indexed: 05/25/2023]
Abstract
We measure the coherent nonlinear response of excitons in a single layer of molybdenum disulfide embedded in hexagonal boron nitride, forming a h-BN/MoS2/ h-BN heterostructure. Using four-wave mixing microscopy and imaging, we correlate the exciton inhomogeneous broadening with the homogeneous one and population lifetime. We find that the exciton dynamics is governed by microscopic disorder on top of the ideal crystal properties. Analyzing the exciton ultrafast density dynamics using amplitude and phase of the response, we investigate the relaxation pathways of the resonantly driven exciton population. The surface protection via encapsulation provides stable monolayer samples with low disorder, avoiding surface contaminations and the resulting exciton broadening and modifications of the dynamics. We identify areas localized to a few microns where the optical response is totally dominated by homogeneous broadening. Across the sample of tens of micrometers, weak inhomogeneous broadening and strain effects are observed, attributed to the remaining interaction with the h-BN and imperfections in the encapsulation process.
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Affiliation(s)
- Tomasz Jakubczyk
- University
Grenoble Alpes, CNRS, Grenoble INP, Institut
Néel, 38000 Grenoble, France
| | - Goutham Nayak
- University
Grenoble Alpes, CNRS, Grenoble INP, Institut
Néel, 38000 Grenoble, France
| | - Lorenzo Scarpelli
- School
of Physics and Astronomy, Cardiff University, The Parade, Cardiff CF24 3AA, United
Kingdom
| | - Wei-Lai Liu
- University
Grenoble Alpes, CNRS, Grenoble INP, Institut
Néel, 38000 Grenoble, France
| | - Sudipta Dubey
- University
Grenoble Alpes, CNRS, Grenoble INP, Institut
Néel, 38000 Grenoble, France
| | - Nedjma Bendiab
- University
Grenoble Alpes, CNRS, Grenoble INP, Institut
Néel, 38000 Grenoble, France
| | - Laëtitia Marty
- University
Grenoble Alpes, CNRS, Grenoble INP, Institut
Néel, 38000 Grenoble, France
| | - Takashi Taniguchi
- National
Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan
| | - Kenji Watanabe
- National
Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan
| | - Francesco Masia
- School
of Physics and Astronomy, Cardiff University, The Parade, Cardiff CF24 3AA, United
Kingdom
| | - Gilles Nogues
- University
Grenoble Alpes, CNRS, Grenoble INP, Institut
Néel, 38000 Grenoble, France
| | - Johann Coraux
- University
Grenoble Alpes, CNRS, Grenoble INP, Institut
Néel, 38000 Grenoble, France
| | - Wolfgang Langbein
- School
of Physics and Astronomy, Cardiff University, The Parade, Cardiff CF24 3AA, United
Kingdom
| | - Julien Renard
- University
Grenoble Alpes, CNRS, Grenoble INP, Institut
Néel, 38000 Grenoble, France
| | - Vincent Bouchiat
- University
Grenoble Alpes, CNRS, Grenoble INP, Institut
Néel, 38000 Grenoble, France
| | - Jacek Kasprzak
- University
Grenoble Alpes, CNRS, Grenoble INP, Institut
Néel, 38000 Grenoble, France
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22
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Molas MR, Gołasa K, Bala Ł, Nogajewski K, Bartos M, Potemski M, Babiński A. Tuning carrier concentration in a superacid treated MoS 2 monolayer. Sci Rep 2019; 9:1989. [PMID: 30760791 PMCID: PMC6374480 DOI: 10.1038/s41598-018-38413-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 12/27/2018] [Indexed: 11/25/2022] Open
Abstract
The effect of bis(trifluoromethane) sulfonimide (TFSI, superacid) treatment on the optical properties of MoS2 monolayers is investigated by means of photoluminescence, reflectance contrast and Raman scattering spectroscopy employed in a broad temperature range. It is shown that when applied multiple times, the treatment results in progressive quenching of the trion emission/absorption and in the redshift of the neutral exciton emission/absorption associated with both the A and B excitonic resonances. Based on this evolution, a trion complex related to the B exciton in monolayer MoS2 is unambiguously identified. A defect-related emission observed at low temperatures also disappears from the spectrum as a result of the treatment. Our observations are attributed to effective passivation of defects on the MoS2 monolayer surface. The passivation reduces the carrier density, which in turn affects the out-of-plane electric field in the sample. The observed tuning of the carrier concentration strongly influences also the Raman scattering in the MoS2 monolayer. An enhancement of Raman scattering at resonant excitation in the vicinity of the A neutral exciton is clearly seen for both the out-of-plane A′1 and in-plane E′ modes. On the contrary, when the excitation is in resonance with a corresponding trion, the Raman scattering features become hardly visible. These results confirm the role of the excitonic charge state plays in the resonance effect of the excitation energy on the Raman scattering in transition metal dichalcogenides.
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Affiliation(s)
- Maciej R Molas
- Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, 02-093, Warszawa, Poland. .,Laboratoire National des Champs Magnétiques Intenses, CNRS-UGA-UPS-INSA-EMFL, 25, avenue des Martyrs, 38042, Grenoble, France.
| | - Katarzyna Gołasa
- Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, 02-093, Warszawa, Poland
| | - Łukasz Bala
- Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, 02-093, Warszawa, Poland.,Laboratoire National des Champs Magnétiques Intenses, CNRS-UGA-UPS-INSA-EMFL, 25, avenue des Martyrs, 38042, Grenoble, France
| | - Karol Nogajewski
- Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, 02-093, Warszawa, Poland.,Laboratoire National des Champs Magnétiques Intenses, CNRS-UGA-UPS-INSA-EMFL, 25, avenue des Martyrs, 38042, Grenoble, France
| | - Miroslav Bartos
- Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, 02-093, Warszawa, Poland
| | - Marek Potemski
- Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, 02-093, Warszawa, Poland.,Laboratoire National des Champs Magnétiques Intenses, CNRS-UGA-UPS-INSA-EMFL, 25, avenue des Martyrs, 38042, Grenoble, France
| | - Adam Babiński
- Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, 02-093, Warszawa, Poland.
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23
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Zuo P, Jiang L, Li X, Ran P, Li B, Song A, Tian M, Ma T, Guo B, Qu L, Lu Y. Enhancing charge transfer with foreign molecules through femtosecond laser induced MoS 2 defect sites for photoluminescence control and SERS enhancement. NANOSCALE 2019; 11:485-494. [PMID: 30543248 DOI: 10.1039/c8nr08785g] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Defect/active site control is crucial for tuning the chemical, optical, and electronic properties of MoS2, which can adjust the performance of MoS2 in application areas such as electronics, optics, catalysis, and molecular sensing. This study presents an effective method of inducing defect/active sites, including micro/nanofractured structures and S atomic vacancies, on monolayer MoS2 flakes by using femtosecond laser pulses, through which physical-chemical adsorption and charge transfer between foreign molecules (O2 or R6G molecules) and MoS2 are enhanced. The enhanced charge transfer between foreign molecules (O2 or R6G) and femtosecond laser-treated MoS2 can enhance the electronic doping effect between them, hence resulting in a photoluminescence photon energy shift (reaching 0.05 eV) of MoS2 and Raman enhancement (reaching 6.4 times) on MoS2 flakes for R6G molecule detection. Finally, photoluminescence control and micropatterns on MoS2 and surface-enhanced-Raman-scattering (SERS) enhancement of MoS2 for organic molecule detection are achieved. The proposed method, which can control the photoluminescence properties and arbitrary micropatterns on MoS2 and enhance its chemicobiological sensing performance for organic/biological molecules, has advantages of simplicity, maskless processing, strong controllability, high precision, and high flexibility, highlighting the superior ability of femtosecond laser pulses to achieve the property control and functionalization of two-dimensional materials.
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Affiliation(s)
- Pei Zuo
- Laser Micro/Nano Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, P.R. China.
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24
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Kim H, Ahn GH, Cho J, Amani M, Mastandrea JP, Groschner CK, Lien DH, Zhao Y, Ager JW, Scott MC, Chrzan DC, Javey A. Synthetic WSe 2 monolayers with high photoluminescence quantum yield. SCIENCE ADVANCES 2019; 5:eaau4728. [PMID: 30613771 PMCID: PMC6314873 DOI: 10.1126/sciadv.aau4728] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 11/28/2018] [Indexed: 05/05/2023]
Abstract
In recent years, there have been tremendous advancements in the growth of monolayer transition metal dichalcogenides (TMDCs) by chemical vapor deposition (CVD). However, obtaining high photoluminescence quantum yield (PL QY), which is the key figure of merit for optoelectronics, is still challenging in the grown monolayers. Specifically, the as-grown monolayers often exhibit lower PL QY than their mechanically exfoliated counterparts. In this work, we demonstrate synthetic tungsten diselenide (WSe2) monolayers with PL QY exceeding that of exfoliated crystals by over an order of magnitude. PL QY of ~60% is obtained in monolayer films grown by CVD, which is the highest reported value to date for WSe2 prepared by any technique. The high optoelectronic quality is enabled by the combination of optimizing growth conditions via tuning the halide promoter ratio, and introducing a simple substrate decoupling method via solvent evaporation, which also mechanically relaxes the grown films. The achievement of scalable WSe2 with high PL QY could potentially enable the emergence of technologically relevant devices at the atomically thin limit.
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Affiliation(s)
- Hyungjin Kim
- Department of Electrical Engineering and Computer Sciences, University of California at Berkeley, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Geun Ho Ahn
- Department of Electrical Engineering and Computer Sciences, University of California at Berkeley, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Joy Cho
- Department of Electrical Engineering and Computer Sciences, University of California at Berkeley, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Matin Amani
- Department of Electrical Engineering and Computer Sciences, University of California at Berkeley, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - James P. Mastandrea
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Materials Science and Engineering, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Catherine K. Groschner
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Materials Science and Engineering, University of California at Berkeley, Berkeley, CA 94720, USA
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Der-Hsien Lien
- Department of Electrical Engineering and Computer Sciences, University of California at Berkeley, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Yingbo Zhao
- Department of Electrical Engineering and Computer Sciences, University of California at Berkeley, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Joel W. Ager
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Materials Science and Engineering, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Mary C. Scott
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Materials Science and Engineering, University of California at Berkeley, Berkeley, CA 94720, USA
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Daryl C. Chrzan
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Materials Science and Engineering, University of California at Berkeley, Berkeley, CA 94720, USA
| | - Ali Javey
- Department of Electrical Engineering and Computer Sciences, University of California at Berkeley, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Corresponding author.
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25
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Sinha S, Sheng Y, Griffiths I, Young NP, Zhou S, Kirkland AI, Porfyrakis K, Warner JH. In Situ Atomic-Level Studies of Gd Atom Release and Migration on Graphene from a Metallofullerene Precursor. ACS NANO 2018; 12:10439-10451. [PMID: 30256088 DOI: 10.1021/acsnano.8b06057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We show how gadolinium (Gd)-based metallofullerene (Gd3N@C80) molecules can be used to create single adatoms and nanoclusters on a graphene surface. An in situ heating holder within an aberration-corrected scanning transmission electron microscope is used to track the adhesion of endohedral metallofullerenes (MFs) to the surface of graphene, followed by Gd metal ejection and diffusion across the surface. Heating to 900 °C is used to promote adatom migration and metal nanocluster formation, enabling direct imaging of the assembly of nanoclusters of Gd. We show that hydrogen can be used to reduce the temperature of MF fragmentation and metal ejection, enabling Gd nanocluster formation on graphene surfaces at temperatures as low as 300 °C. The process of MF fragmentation and metal ejection is captured in situ and reveals that after metal release, the C80 cage opens further and fuses with the surface monolayer carbon glass on graphene, creating a highly stable carbon layer for further Gd adatom adhesion. Small voids and defects (∼1 nm) in the surface carbon glass act as trapping sites for Gd atoms, leading to atomic self-assembly of 2D monolayer Gd clusters. These results show that MFs can adhere to graphene surfaces at temperatures well above their bulk sublimation point, indicating that the surface bound MFs have strong adhesion to dangling bonds on graphene surfaces. The ability to create dispersed single Gd adatoms and Gd nanoclusters on graphene may have impact in spintronics and magnetism.
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Affiliation(s)
- Sapna Sinha
- Department of Materials , University of Oxford , 16 Parks Road , Oxford OX1 3PH , United Kingdom
| | - Yuewen Sheng
- Department of Materials , University of Oxford , 16 Parks Road , Oxford OX1 3PH , United Kingdom
| | - Ian Griffiths
- Department of Materials , University of Oxford , 16 Parks Road , Oxford OX1 3PH , United Kingdom
| | - Neil P Young
- Department of Materials , University of Oxford , 16 Parks Road , Oxford OX1 3PH , United Kingdom
| | - Si Zhou
- Department of Materials , University of Oxford , 16 Parks Road , Oxford OX1 3PH , United Kingdom
| | - Angus I Kirkland
- Department of Materials , University of Oxford , 16 Parks Road , Oxford OX1 3PH , United Kingdom
- Electron Physical Sciences Imaging Center , Diamond Light Source Ltd , Didcot OX11 0DE , United Kingdom
| | - Kyriakos Porfyrakis
- Department of Materials , University of Oxford , 16 Parks Road , Oxford OX1 3PH , United Kingdom
| | - Jamie H Warner
- Department of Materials , University of Oxford , 16 Parks Road , Oxford OX1 3PH , United Kingdom
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26
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Jha PK, Shitrit N, Ren X, Wang Y, Zhang X. Spontaneous Exciton Valley Coherence in Transition Metal Dichalcogenide Monolayers Interfaced with an Anisotropic Metasurface. PHYSICAL REVIEW LETTERS 2018; 121:116102. [PMID: 30265090 DOI: 10.1103/physrevlett.121.116102] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Indexed: 05/13/2023]
Abstract
The control of the exciton intervalley coherence renders transition metal dichalcogenides monolayers promising candidates for quantum information science. So far, generating intervalley coherence has the need for an external coherent field. Here, we theoretically demonstrate spontaneous generation (i.e., without any external field) of exciton intervalley coherence. We achieve this by manipulating the vacuum field in the vicinity of the monolayer with a designed polarization-dependent metasurface, inducing an anisotropic decay rate for in-plane excitonic dipoles. Harnessing quantum coherence and interference effects in two-dimensional materials may provide the route for novel quantum valleytronic devices.
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Affiliation(s)
- Pankaj K Jha
- NSF Nanoscale Science and Engineering Center (NSEC), 3112 Etcheverry Hall, University of California, Berkeley, California 94720, USA
| | - Nir Shitrit
- NSF Nanoscale Science and Engineering Center (NSEC), 3112 Etcheverry Hall, University of California, Berkeley, California 94720, USA
| | - Xuexin Ren
- NSF Nanoscale Science and Engineering Center (NSEC), 3112 Etcheverry Hall, University of California, Berkeley, California 94720, USA
| | - Yuan Wang
- NSF Nanoscale Science and Engineering Center (NSEC), 3112 Etcheverry Hall, University of California, Berkeley, California 94720, USA
| | - Xiang Zhang
- NSF Nanoscale Science and Engineering Center (NSEC), 3112 Etcheverry Hall, University of California, Berkeley, California 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA
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27
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Kiriya D, Hijikata Y, Pirillo J, Kitaura R, Murai A, Ashida A, Yoshimura T, Fujimura N. Systematic Study of Photoluminescence Enhancement in Monolayer Molybdenum Disulfide by Acid Treatment. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:10243-10249. [PMID: 30099877 DOI: 10.1021/acs.langmuir.8b01425] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Monolayer molybdenum disulfide (MoS2) is an atomically thin semiconducting material with a direct band gap. This physical property is attributable to atomically thin optical devices such as sensors, light-emitting devices, and photovoltaic cells. Recently, a near-unity photoluminescence (PL) quantum yield of a monolayer MoS2 was demonstrated via a treatment with a molecular acid, bis(trifluoromethane)sulfonimide (TFSI); however, the mechanism still remains a mystery. Here, we work on PL enhancement of monolayer MoS2 by treatment of Brønsted acids (TFSI and sulfuric acid (H2SO4)) to identify the importance of the protonated environment. In TFSI as an acid, different solvents-1,2-dichloroethane (DCE), acetonitrile, and water-were studied, as they show quite different acidity in solution. All of the solvents showed PL enhancement, and the highest was observed in DCE. This behavior in DCE would be due to the higher acidity than others have. Acids from different anions can also be studied in water as a common solvent. Both TFSI and H2SO4 showed similar PL enhancement (∼4-8 enhancement) at the same proton concentration, indicating that the proton is a key factor to enhance the PL intensity. Finally, we considered another cation, Li+ from Li2SO4, instead of H2SO4, in water. Although Li and H atoms showed similar binding energy on MoS2 from theoretical calculations, Li2SO4 treatment showed little PL enhancement; only coexisting H2SO4 reproduced the enhancement. This study demonstrated the importance of a protonated environment to increase the PL intensity of monolayer MoS2. The study will lead to a solution to achieve high optical quality and to implementation for atomically thin optical devices.
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Affiliation(s)
- Daisuke Kiriya
- Department of Physics and Electronics , Osaka Prefecture University , 1-1 Gakuen-cho , Naka-ku, Sakai-shi , Osaka 599-8531 , Japan
- JST, PRESTO , 4-1-8 Honcho , Kawaguchi , Saitama 332-0012 , Japan
| | | | | | | | - Akihiko Murai
- Department of Physics and Electronics , Osaka Prefecture University , 1-1 Gakuen-cho , Naka-ku, Sakai-shi , Osaka 599-8531 , Japan
| | - Atsushi Ashida
- Department of Physics and Electronics , Osaka Prefecture University , 1-1 Gakuen-cho , Naka-ku, Sakai-shi , Osaka 599-8531 , Japan
| | - Takeshi Yoshimura
- Department of Physics and Electronics , Osaka Prefecture University , 1-1 Gakuen-cho , Naka-ku, Sakai-shi , Osaka 599-8531 , Japan
| | - Norifumi Fujimura
- Department of Physics and Electronics , Osaka Prefecture University , 1-1 Gakuen-cho , Naka-ku, Sakai-shi , Osaka 599-8531 , Japan
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28
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Bertolazzi S, Gobbi M, Zhao Y, Backes C, Samorì P. Molecular chemistry approaches for tuning the properties of two-dimensional transition metal dichalcogenides. Chem Soc Rev 2018; 47:6845-6888. [PMID: 30043037 DOI: 10.1039/c8cs00169c] [Citation(s) in RCA: 118] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Two-dimensional (2D) semiconductors, such as ultrathin layers of transition metal dichalcogenides (TMDs), offer a unique combination of electronic, optical and mechanical properties, and hold potential to enable a host of new device applications spanning from flexible/wearable (opto)electronics to energy-harvesting and sensing technologies. A critical requirement for developing practical and reliable electronic devices based on semiconducting TMDs consists in achieving a full control over their charge-carrier polarity and doping. Inconveniently, such a challenging task cannot be accomplished by means of well-established doping techniques (e.g. ion implantation and diffusion), which unavoidably damage the 2D crystals resulting in degraded device performances. Nowadays, a number of alternatives are being investigated, including various (supra)molecular chemistry approaches relying on the combination of 2D semiconductors with electroactive donor/acceptor molecules. As yet, a large variety of molecular systems have been utilized for functionalizing 2D TMDs via both covalent and non-covalent interactions. Such research endeavours enabled not only the tuning of the charge-carrier doping but also the engineering of the optical, electronic, magnetic, thermal and sensing properties of semiconducting TMDs for specific device applications. Here, we will review the most enlightening recent advancements in experimental (supra)molecular chemistry methods for tailoring the properties of atomically-thin TMDs - in the form of substrate-supported or solution-dispersed nanosheets - and we will discuss the opportunities and the challenges towards the realization of novel hybrid materials and devices based on 2D semiconductors and molecular systems.
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Affiliation(s)
- Simone Bertolazzi
- Université de Strasbourg, CNRS, ISIS, 8 alleé Gaspard Monge, 67000 Strasbourg, France.
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Schwermann C, Stiehm T, Tonndorf P, Schneider R, Schmidt R, Kern J, Michaelis de Vasconcellos S, Bratschitsch R, Doltsinis NL. Incorporation of oxygen atoms as a mechanism for photoluminescence enhancement of chemically treated MoS 2. Phys Chem Chem Phys 2018; 20:16918-16923. [PMID: 29904778 DOI: 10.1039/c8cp03052a] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Chemical treatments to enhance photoluminescence (PL) in MoS2 have been explored extensively by experimental means in recent years. However, satisfactory theoretical explanations of the underlying mechanisms remain elusive. In this work, the surface reactions of the superacid bis(trifluoromethane)-sulfonimide (TFSI), hydrogen peroxide (H2O2), molecular oxygen (O2), and sulfuric acid (H2SO4) on a defective MoS2 monolayer have been studied using first principles calculations. An oxygen transfer reaction into a sulfur vacancy with a low activation barrier and thus significant reaction rates already at room temperature has been found. Band structure unfolding techniques show that the incorporation of oxygen atoms into sulfur vacancies restores the band structure of pristine MoS2, which is predicted to have a high PL quantum yield. PL spectroscopy is used to examine the effect of chemical treatment on PL intensity. Our experimental findings support our theoretical predictions, as PL in MoS2 is enhanced by up to a factor 20 after treatment with H2O2 or H2SO4, while the spectral shape is only slightly altered.
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Affiliation(s)
- Christian Schwermann
- Institute for Solid State Theory and Center for Multiscale Theory and Computation, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Straße 10, 48149 Münster, Germany
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30
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Pu J, Takenobu T. Monolayer Transition Metal Dichalcogenides as Light Sources. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1707627. [PMID: 29900597 DOI: 10.1002/adma.201707627] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 02/21/2018] [Indexed: 05/25/2023]
Abstract
Reducing the dimensions of materials is one of the key approaches to discovering novel optical phenomena. The recent emergence of 2D transition metal dichalcogenides (TMDCs) has provided a promising platform for exploring new optoelectronic device applications, with their tunable electronic properties, structural controllability, and unique spin valley-coupled systems. This progress report provides an overview of recent advances in TMDC-based light-emitting devices discussed from several aspects in terms of device concepts, material designs, device fabrication, and their diverse functionalities. First, the advantages of TMDCs used in light-emitting devices and their possible functionalities are presented. Second, conventional approaches for fabricating TMDC light-emitting devices are emphasized, followed by introducing a newly established, versatile method for generating light emission in TMDCs. Third, current growing technologies for heterostructure fabrication, in which distinct TMDCs are vertically stacked or laterally stitched, are explained as a possible means for designing high-performance light-emitting devices. Finally, utilizing the topological features of TMDCs, the challenges for controlling circularly polarized light emission and its device applications are discussed from both theoretical and experimental points of view.
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Affiliation(s)
- Jiang Pu
- Department of Applied Physics, Nagoya University, Nagoya, 464-8603, Japan
| | - Taishi Takenobu
- Department of Applied Physics, Nagoya University, Nagoya, 464-8603, Japan
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31
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Ji X, Zhou P, Zhong L, Xu A, Tsang ACO, Chan PKL. Smart Surgical Catheter for C-Reactive Protein Sensing Based on an Imperceptible Organic Transistor. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2018; 5:1701053. [PMID: 29938182 PMCID: PMC6010781 DOI: 10.1002/advs.201701053] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 03/29/2018] [Indexed: 05/25/2023]
Abstract
Organic field-effect transistors (OFETs)-based sensors have a great potential to be integrated with the next generation smart surgical tools for monitoring different real-time signals during surgery. However, allowing ultraflexible OFETs to have compatibility with standard medical sterilization procedures remains challenging. A novel capsule-like OFET structure is demonstrated by utilizing the fluoropolymer CYTOP to serve both encapsulation and peeling-off enhancement purposes. By adapting a thermally stable organic semiconductor, 2,10-diphenylbis[1]benzothieno[2,3-d;2',3'-d']naphtho[2,3-b;6,7-b']dithiophene (DPh-BBTNDT), these devices show excellent stability in their electrical performance after sterilizing under boiling water and 100 °C-saturated steam for 30 min. The ultrathin thickness (630 nm) enables the device to have superb mechanical flexibility with smallest bending radius down to 1.5 µm, which is essential for application on the highly tortuous medical catheter inside the human body. By immobilizing anti-human C-reactive protein (CRP) (an inflammation biomarker) monoclonal antibody on an extended gate of the OFET, a sensitivity for detecting CRP antigen down to 1 µg mL-1 can be achieved. An ecofriendly water floatation method realized by employing the wettability difference between CYTOP and polyacrylonitrile (PAN) can be used to transfer the device on a ventricular catheter, which successfully distinguishes an inflammatory patient from a healthy one.
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Affiliation(s)
- Xudong Ji
- Department of Mechanical EngineeringThe University of Hong KongHong Kong
| | - Pengcheng Zhou
- State Key Laboratory of Pharmaceutical BiotechnologyThe University of Hong KongHong Kong
- Department of MedicineThe University of Hong KongHong Kong
| | - Ling Zhong
- State Key Laboratory of Pharmaceutical BiotechnologyThe University of Hong KongHong Kong
- Department of MedicineThe University of Hong KongHong Kong
| | - Aimin Xu
- State Key Laboratory of Pharmaceutical BiotechnologyThe University of Hong KongHong Kong
- Department of MedicineThe University of Hong KongHong Kong
- China Department of Pharmacology and PharmacyThe University of Hong KongHong Kong
| | | | - Paddy K. L. Chan
- Department of Mechanical EngineeringThe University of Hong KongHong Kong
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32
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Chen X, Wang Z, Wang L, Wang HY, Yue YY, Wang H, Wang XP, Wee ATS, Qiu CW, Sun HB. Investigating the dynamics of excitons in monolayer WSe 2 before and after organic super acid treatment. NANOSCALE 2018; 10:9346-9352. [PMID: 29737993 DOI: 10.1039/c8nr00774h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Due to the large photoluminescence quantum yield, high mobility and good stability, organic super acid treated two-dimensional WSe2 has drawn much attention. However, reports about the influence of organic super acid treatment on the dynamic processes of excitons of monolayer WSe2 are still rare. In this work, through the broadband transient absorption spectra obtained using a femtosecond pump-probe system, we determine the dynamics of A' and C excitons in monolayer and bulk WSe2 at room temperature. Besides this, we also observe the relaxation process of the holes between the two spin split states in the valence band maximum in organic super acid treated monolayer WSe2. We find that the organic super acid treatment on monolayer WSe2 does not change the peak positions of the exciton states, while those bleaching peaks' intensities increase significantly due to the enhancement of oscillator strength for exciton states, corresponding to stronger steady-state photoluminescence. This could be attributed to the strain release induced by the defect repairing effect during the organic super acid treatment process.
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Affiliation(s)
- Xin Chen
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
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33
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Wang Z, Jingjing Q, Wang X, Zhang Z, Chen Y, Huang X, Huang W. Two-dimensional light-emitting materials: preparation, properties and applications. Chem Soc Rev 2018; 47:6128-6174. [DOI: 10.1039/c8cs00332g] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We review the recent development in two-dimensional (2D) light-emitting materials and describe their preparation methods, optical/optoelectronic properties and applications.
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Affiliation(s)
- Zhiwei Wang
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
| | - Qiu Jingjing
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
| | - Xiaoshan Wang
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
| | - Zhipeng Zhang
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
| | - Yonghua Chen
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
| | - Xiao Huang
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
| | - Wei Huang
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
- Shaanxi Institute of Flexible Electronics (SIFE)
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34
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Zeng Y, Chen W, Tang B, Liao J, Lou J, Chen Q. Synergetic photoluminescence enhancement of monolayer MoS2via surface plasmon resonance and defect repair. RSC Adv 2018; 8:23591-23598. [PMID: 35540286 PMCID: PMC9081737 DOI: 10.1039/c8ra03779e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 06/21/2018] [Indexed: 11/23/2022] Open
Abstract
The weak light-absorption and low quantum yield (QY) in monolayer MoS2 are great challenges for the applications of this material in practical optoelectronic devices. Here, we report on a synergistic strategy to obtain highly enhanced photoluminescence (PL) of monolayer MoS2 by simultaneously improving the intensity of the electromagnetic field around MoS2 and the QY of MoS2. Self-assembled sub-monolayer Au nanoparticles underneath the monolayer MoS2 and bis(trifluoromethane)sulfonimide (TFSI) treatment to the MoS2 surface are used to boost the excitation field and the QY, respectively. An enhancement factor of the PL intensity as high as 280 is achieved. The enhancement mechanisms are analyzed by inspecting the contribution of the PL spectra from A excitons and A− trions under different conditions. Our study takes a further step to developing high-performance optoelectronic devices based on monolayer MoS2. A synergistic strategy is reported to obtain a highly enhanced photoluminescence (PL) of monolayer MoS2 by simultaneously improving the intensity of the electromagnetic field around MoS2 and the QY of MoS2.![]()
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Affiliation(s)
- Yi Zeng
- Key Laboratory for the Physics and Chemistry of Nanodevices
- Department of Electronics
- Peking University
- Beijing 100871
- China
| | - Weibing Chen
- Department of Materials Science and NanoEngineering
- Rice University
- Houston
- USA
| | - Bin Tang
- Key Laboratory for the Physics and Chemistry of Nanodevices
- Department of Electronics
- Peking University
- Beijing 100871
- China
| | - Jianhui Liao
- Key Laboratory for the Physics and Chemistry of Nanodevices
- Department of Electronics
- Peking University
- Beijing 100871
- China
| | - Jun Lou
- Department of Materials Science and NanoEngineering
- Rice University
- Houston
- USA
| | - Qing Chen
- Key Laboratory for the Physics and Chemistry of Nanodevices
- Department of Electronics
- Peking University
- Beijing 100871
- China
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