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Coelho PM. Magnetic doping in transition metal dichalcogenides. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:203001. [PMID: 38324890 DOI: 10.1088/1361-648x/ad271b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Accepted: 02/07/2024] [Indexed: 02/09/2024]
Abstract
Transition metal dichalcogenides (TMDCs) are materials with unique electronic properties due to their two-dimensional nature. Recently, there is a large and growing interest in synthesizing ferromagnetic TMDCs for applications in electronic devices and spintronics. Apart from intrinsically magnetic examples, modification via either intrinsic defects or external dopants may induce ferromagnetism in non-magnetic TMDCs and, hence expand the application of these materials. Here, we review recent experimental work on intrinsically non-magnetic TMDCs that present ferromagnetism as a consequence of either intrinsic defects or doping via self-flux approach, ion implantation or e-beam evaporation. The experimental work discussed here is organized by modification/doping mechanism. We also review current work on density functional theory calculations that predict ferromagnetism in doped systems, which also serve as preliminary data for the choice of new doped TMDCs to be explored experimentally. Implementing a controlled process to induce magnetism in two-dimensional materials is key for technological development and this topical review discusses the fundamental procedures while presenting promising materials to be investigated in order to achieve this goal.
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Affiliation(s)
- Paula Mariel Coelho
- Department of Physics, University of North Florida, Jacksonville, FL, United States of America
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2
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Dai B, Su Y, Guo Y, Wu C, Xie Y. Recent Strategies for the Synthesis of Phase-Pure Ultrathin 1T/1T' Transition Metal Dichalcogenide Nanosheets. Chem Rev 2024; 124:420-454. [PMID: 38146851 DOI: 10.1021/acs.chemrev.3c00422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
The past few decades have witnessed a notable increase in transition metal dichalcogenide (TMD) related research not only because of the large family of TMD candidates but also because of the various polytypes that arise from the monolayer configuration and layer stacking order. The peculiar physicochemical properties of TMD nanosheets enable an enormous range of applications from fundamental science to industrial technologies based on the preparation of high-quality TMDs. For polymorphic TMDs, the 1T/1T' phase is particularly intriguing because of the enriched density of states, and thus facilitates fruitful chemistry. Herein, we comprehensively discuss the most recent strategies for direct synthesis of phase-pure 1T/1T' TMD nanosheets such as mechanical exfoliation, chemical vapor deposition, wet chemical synthesis, atomic layer deposition, and more. We also review frequently adopted methods for phase engineering in TMD nanosheets ranging from chemical doping and alloying, to charge injection, and irradiation with optical or charged particle beams. Prior to the synthesis methods, we discuss the configuration of TMDs as well as the characterization tools mostly used in experiments. Finally, we discuss the current challenges and opportunities as well as emphasize the promising fields for the future development.
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Affiliation(s)
- Baohu Dai
- Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Yueqi Su
- Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Yuqiao Guo
- Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Changzheng Wu
- Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Yi Xie
- Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
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3
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Bui MN, Rost S, Auge M, Zhou L, Friedrich C, Blügel S, Kretschmer S, Krasheninnikov AV, Watanabe K, Taniguchi T, Hofsäss HC, Grützmacher D, Kardynał BE. Optical Properties of MoSe 2 Monolayer Implanted with Ultra-Low-Energy Cr Ions. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 37432886 PMCID: PMC10375475 DOI: 10.1021/acsami.3c05366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/13/2023]
Abstract
This paper explores the optical properties of an exfoliated MoSe2 monolayer implanted with Cr+ ions, accelerated to 25 eV. Photoluminescence of the implanted MoSe2 reveals an emission line from Cr-related defects that is present only under weak electron doping. Unlike band-to-band transition, the Cr-introduced emission is characterized by nonzero activation energy, long lifetimes, and weak response to the magnetic field. To rationalize the experimental results and get insights into the atomic structure of the defects, we modeled the Cr-ion irradiation process using ab initio molecular dynamics simulations followed by the electronic structure calculations of the system with defects. The experimental and theoretical results suggest that the recombination of electrons on the acceptors, which could be introduced by the Cr implantation-induced defects, with the valence band holes is the most likely origin of the low-energy emission. Our results demonstrate the potential of low-energy ion implantation as a tool to tailor the properties of two-dimensional (2D) materials by doping.
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Affiliation(s)
- Minh N Bui
- Peter Grünberg Institute 9 (PGI-9), Forschungszentrum Jülich, 52425 Jülich, Germany
- Department of Physics, RWTH Aachen University, 52074 Aachen, Germany
| | - Stefan Rost
- Department of Physics, RWTH Aachen University, 52074 Aachen, Germany
- Peter Grünberg Institute 1 (PGI-1) and Institute for Advanced Simulation 1 (IAS-1), Forschungszentrum Jülich and JARA, 52425 Jülich, Germany
| | - Manuel Auge
- II. Institute of Physics, University of Göttingen, 37077 Göttingen, Germany
| | - Lanqing Zhou
- Peter Grünberg Institute 9 (PGI-9), Forschungszentrum Jülich, 52425 Jülich, Germany
- Department of Physics, RWTH Aachen University, 52074 Aachen, Germany
| | | | - Stefan Blügel
- Department of Physics, RWTH Aachen University, 52074 Aachen, Germany
- II. Institute of Physics, University of Göttingen, 37077 Göttingen, Germany
| | - Silvan Kretschmer
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - Arkady V Krasheninnikov
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
- Department of Applied Physics, Aalto University School of Science, P.O. Box 11100, 00076 Aalto, Finland
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Hans C Hofsäss
- II. Institute of Physics, University of Göttingen, 37077 Göttingen, Germany
| | - Detlev Grützmacher
- Peter Grünberg Institute 9 (PGI-9), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Beata E Kardynał
- Peter Grünberg Institute 9 (PGI-9), Forschungszentrum Jülich, 52425 Jülich, Germany
- Department of Physics, RWTH Aachen University, 52074 Aachen, Germany
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4
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Xiao Y, Xiong C, Chen MM, Wang S, Fu L, Zhang X. Structure modulation of two-dimensional transition metal chalcogenides: recent advances in methodology, mechanism and applications. Chem Soc Rev 2023; 52:1215-1272. [PMID: 36601686 DOI: 10.1039/d1cs01016f] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Together with the development of two-dimensional (2D) materials, transition metal dichalcogenides (TMDs) have become one of the most popular series of model materials for fundamental sciences and practical applications. Due to the ever-growing requirements of customization and multi-function, dozens of modulated structures have been introduced in TMDs. In this review, we present a systematic and comprehensive overview of the structure modulation of TMDs, including point, linear and out-of-plane structures, following and updating the conventional classification for silicon and related bulk semiconductors. In particular, we focus on the structural characteristics of modulated TMD structures and analyse the corresponding root causes. We also summarize the recent progress in modulating methods, mechanisms, properties and applications based on modulated TMD structures. Finally, we demonstrate challenges and prospects in the structure modulation of TMDs and forecast potential directions about what and how breakthroughs can be achieved.
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Affiliation(s)
- Yao Xiao
- Collaborative Innovation Centre for Advanced Organic Chemical Materials Co-Constructed by the Province and Ministry, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, P. R. China.
| | - Chengyi Xiong
- Collaborative Innovation Centre for Advanced Organic Chemical Materials Co-Constructed by the Province and Ministry, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, P. R. China.
| | - Miao-Miao Chen
- Collaborative Innovation Centre for Advanced Organic Chemical Materials Co-Constructed by the Province and Ministry, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, P. R. China.
| | - Shengfu Wang
- Collaborative Innovation Centre for Advanced Organic Chemical Materials Co-Constructed by the Province and Ministry, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, P. R. China.
| | - Lei Fu
- The Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, P. R. China. .,College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, P. R. China.
| | - Xiuhua Zhang
- Collaborative Innovation Centre for Advanced Organic Chemical Materials Co-Constructed by the Province and Ministry, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, P. R. China.
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5
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Giri A, Park G, Jeong U. Layer-Structured Anisotropic Metal Chalcogenides: Recent Advances in Synthesis, Modulation, and Applications. Chem Rev 2023; 123:3329-3442. [PMID: 36719999 PMCID: PMC10103142 DOI: 10.1021/acs.chemrev.2c00455] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The unique electronic and catalytic properties emerging from low symmetry anisotropic (1D and 2D) metal chalcogenides (MCs) have generated tremendous interest for use in next generation electronics, optoelectronics, electrochemical energy storage devices, and chemical sensing devices. Despite many proof-of-concept demonstrations so far, the full potential of anisotropic chalcogenides has yet to be investigated. This article provides a comprehensive overview of the recent progress made in the synthesis, mechanistic understanding, property modulation strategies, and applications of the anisotropic chalcogenides. It begins with an introduction to the basic crystal structures, and then the unique physical and chemical properties of 1D and 2D MCs. Controlled synthetic routes for anisotropic MC crystals are summarized with example advances in the solution-phase synthesis, vapor-phase synthesis, and exfoliation. Several important approaches to modulate dimensions, phases, compositions, defects, and heterostructures of anisotropic MCs are discussed. Recent significant advances in applications are highlighted for electronics, optoelectronic devices, catalysts, batteries, supercapacitors, sensing platforms, and thermoelectric devices. The article ends with prospects for future opportunities and challenges to be addressed in the academic research and practical engineering of anisotropic MCs.
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Affiliation(s)
- Anupam Giri
- Department of Chemistry, Faculty of Science, University of Allahabad, Prayagraj, UP-211002, India
| | - Gyeongbae Park
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Cheongam-Ro 77, Nam-Gu, Pohang, Gyeongbuk790-784, Korea.,Functional Materials and Components R&D Group, Korea Institute of Industrial Technology, Gwahakdanji-ro 137-41, Sacheon-myeon, Gangneung, Gangwon-do25440, Republic of Korea
| | - Unyong Jeong
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Cheongam-Ro 77, Nam-Gu, Pohang, Gyeongbuk790-784, Korea
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Lasek K, Li J, Ghorbani-Asl M, Khatun S, Alanwoko O, Pathirage V, Krasheninnikov AV, Batzill M. Formation of In-Plane Semiconductor-Metal Contacts in 2D Platinum Telluride by Converting PtTe 2 to Pt 2Te 2. NANO LETTERS 2022; 22:9571-9577. [PMID: 36399113 DOI: 10.1021/acs.nanolett.2c03715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Monolayer PtTe2 is a narrow gap semiconductor while Pt2Te2 is a metal. Here we show that the former can be transformed into the latter by reaction with vapor-deposited Pt atoms. The transformation occurs by nucleating the Pt2Te2 phase within PtTe2 islands, so that a metal-semiconductor junction is formed. A flat band structure is found with the Fermi level of the metal aligning with that of the intrinsically p-doped PtTe2. This is achieved by an interface dipole that accommodates the ∼0.2 eV shift in the work functions of the two materials. First-principles calculations indicate that the origin of the interface dipole is the atomic scale charge redistributions at the heterojunction. The demonstrated compositional phase transformation of a 2D semiconductor into a 2D metal is a promising approach for making in-plane metal contacts that are required for efficient charge injection and is of particular interest for semiconductors with large spin-orbit coupling, like PtTe2.
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Affiliation(s)
- Kinga Lasek
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Jingfeng Li
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Mahdi Ghorbani-Asl
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - Salma Khatun
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Onyedikachi Alanwoko
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Vimukthi Pathirage
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
| | - Arkady V Krasheninnikov
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
- Department of Applied Physics, Aalto University, P.O. Box 11100, 00076 Aalto, Finland
| | - Matthias Batzill
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
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Yuan M, Tan R, Li M, Jin C, Jing T, Sun Q. Tunable magnetocrystalline anisotropy of two-dimensional Fe 3GeTe 2 with adsorbed 5d-transition metal. Phys Chem Chem Phys 2022; 24:21470-21476. [PMID: 36048558 DOI: 10.1039/d2cp02083a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The demand for ultra-compact spintronic devices with lower energy consumption and higher storage density requires two-dimensional (2D) magnetic materials with tunable magnetocrystalline anisotropy (MCA) energy. Employing first-principles calculations, we have investigated the influence of W atom adsorption and biaxial strain on the magnetic properties of layered Fe3GeTe2. We demonstrate that the adsorption mode and applied strain play a critical role in determining their MCA. The Fe3GeTe2 adsorbed with W atoms undergoes a change in spin reorientation from out-of-plane to in-plane magnetization, yielding a colossal MCA up to -13.112 erg cm-2. The dominant contribution to these unexpected changes mainly arises from the W atoms with emerged magnetism and large SOC. Moreover, our results reveal distinct strain-driven modulation behaviors of the MCA in different adsorption configurations. The underlying atomistic mechanism mainly involves the alteration of various W-derived 5d-orbital states under the strain effect, leading to competitive changes of the corresponding spin-orbit coupling energies between the spin-parallel and spin-flip channels. Our findings not only provide useful guidance in optimizing the MCA performance of 2D magnetic crystals but also highlight the potential of W-adsorbed Fe3GeTe2 in the applications of new-generation magnetic memory storage devices.
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Affiliation(s)
- Miaojia Yuan
- School of Science, Shandong Jianzhu University, Jinan, Shandong, 250101, China.
| | - Ruishan Tan
- School of Science, Shandong Jianzhu University, Jinan, Shandong, 250101, China.
| | - Mengmeng Li
- School of Science, Shandong Jianzhu University, Jinan, Shandong, 250101, China.
| | - Cui Jin
- School of Science, Shandong Jianzhu University, Jinan, Shandong, 250101, China.
| | - Tao Jing
- College of Science, Kaili University, Kaili, Guizhou, 556011, China
| | - Qilong Sun
- School of Science, Shandong Jianzhu University, Jinan, Shandong, 250101, China.
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Liu H, Silva WC, Santana Gonçalves de Souza L, Veiga AG, Seixas L, Fujisawa K, Kahn E, Zhang T, Zhang F, Yu Z, Thompson K, Lei Y, de Matos CJS, Rocco MLM, Terrones M, Grasseschi D. 3d transition metal coordination on monolayer MoS 2: a facile doping method to functionalize surfaces. NANOSCALE 2022; 14:10801-10815. [PMID: 35735180 DOI: 10.1039/d2nr01132h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Two-dimensional materials (2DM) have attracted much interest due to their distinct optical, electronic, and catalytic properties. These properties can be tuned by a range of methods including substitutional doping and, as recently demonstrated, by surface functionalization with single atoms, thus increasing the 2DM portfolio. We theoretically and experimentally describe the coordination reaction between MoS2 monolayers and 3d transition metals (TMs), exploring their nature and MoS2-TM interactions. Density functional theory calculations, X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy point to the formation of MoS2-TM coordination complexes, where the adsorption energy for 3d TMs resembles the crystal-field (CF) stabilization energy for weak-field complexes. Pearson's theory for hard-soft acid-base and ligand-field theory were used to discuss the periodic trends of 3d TM coordination on MoS2 monolayer surfaces. We found that softer acids with higher ligand field stabilization energy, such as Ni2+, tend to form bonds with more covalent character with MoS2, which can be considered a soft base. On the other hand, harder acids, such as Cr3+, tend to form more ionic bonds. Additionally, we studied the trends in charge transfer and doping observed from XPS and PL results, where metals like Ni led to n-type doping. In contrast, Cu functionalization results in p-type doping. Therefore, the formation of coordination complexes on TMD's surface is a potentially effective way to control and understand the nature of single-atom functionalization of TMD monolayers without relying on or creating new defects.
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Affiliation(s)
- He Liu
- Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA.
| | - Walner Costa Silva
- Institute of Chemistry, Federal University of Rio de Janeiro (UFRJ), 21941-909, Rio de Janeiro, Brazil.
| | | | - Amanda Garcez Veiga
- Institute of Chemistry, Federal University of Rio de Janeiro (UFRJ), 21941-909, Rio de Janeiro, Brazil.
| | - Leandro Seixas
- MackGraphe-Graphene and Nanomaterials Research Center, Mackenzie Presbyterian Institute, 01302-907, São Paulo, Brazil
- Engineering School, Mackenzie Presbyterian University, 01302-907, São Paulo, Brazil
| | - Kazunori Fujisawa
- Research Initiative for Supra-Materials (RISM), Shinshu University, 4-17-1 Wakasato, Nagano, 380-8553, Japan
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Ethan Kahn
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Tianyi Zhang
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Fu Zhang
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Zhuohang Yu
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Katherine Thompson
- Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA.
| | - Yu Lei
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Christiano J S de Matos
- MackGraphe-Graphene and Nanomaterials Research Center, Mackenzie Presbyterian Institute, 01302-907, São Paulo, Brazil
- Engineering School, Mackenzie Presbyterian University, 01302-907, São Paulo, Brazil
| | - Maria Luiza M Rocco
- Institute of Chemistry, Federal University of Rio de Janeiro (UFRJ), 21941-909, Rio de Janeiro, Brazil.
| | - Mauricio Terrones
- Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA.
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Daniel Grasseschi
- Institute of Chemistry, Federal University of Rio de Janeiro (UFRJ), 21941-909, Rio de Janeiro, Brazil.
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Hennessy M, O'Connell EN, Auge M, Moynihan E, Hofsäss H, Bangert U. Quantification of Ion-Implanted Single-Atom Dopants in Monolayer MoS 2 via HAADF STEM Using the TEMUL Toolkit. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2022; 28:1-10. [PMID: 35722923 DOI: 10.1017/s1431927622000757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In recent years, atomic resolution imaging of two-dimensional (2D) materials using scanning transmission electron microscopy (STEM) has become routine. Individual dopant atoms in 2D materials can be located and identified using their contrast in annular dark-field (ADF) STEM. However, in order to understand the effect of these dopant atoms on the host material, there is now the need to locate and quantify them on a larger scale. In this work, we analyze STEM images of MoS2 monolayers that have been ion-implanted with chromium at ultra-low energies. We use functions from the open-source TEMUL Toolkit to create and refine an atomic model of an experimental image based on the positions and intensities of the atomic columns in the image. We then use the refined model to determine the likely composition of each atomic site. Surface contamination stemming from the sample preparation of 2D materials can prevent accurate quantitative identification of individual atoms. We disregard atomic sites from regions of the image with hydrocarbon surface contamination to demonstrate that images acquired using contaminated samples can give significant atom statistics from their clean regions, and can be used to calculate the retention rate of the implanted ions within the host lattice. We find that some of the implanted chromium ions have been successfully integrated into the MoS2 lattice, with 4.1% of molybdenum atoms in the transition metal sublattice replaced with chromium.
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Affiliation(s)
- Michael Hennessy
- Department of Physics, Bernal Institute, School of Natural Sciences, University of Limerick, Limerick, Ireland
| | - Eoghan N O'Connell
- Department of Physics, Bernal Institute, School of Natural Sciences, University of Limerick, Limerick, Ireland
| | - Manuel Auge
- II. Institute of Physics, University of Göttingen, 37077 Göttingen, Germany
| | - Eoin Moynihan
- Department of Physics, Bernal Institute, School of Natural Sciences, University of Limerick, Limerick, Ireland
| | - Hans Hofsäss
- II. Institute of Physics, University of Göttingen, 37077 Göttingen, Germany
| | - Ursel Bangert
- Department of Physics, Bernal Institute, School of Natural Sciences, University of Limerick, Limerick, Ireland
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10
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Zhu YN, Li XB, Zhang Q, Peng F. Which Is Better for Hydrogen Evolution on Metal@MoS 2 Heterostructures from a Theoretical Perspective: Single Atom or Monolayer? ACS APPLIED MATERIALS & INTERFACES 2022; 14:25592-25600. [PMID: 35623062 DOI: 10.1021/acsami.2c06698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Single atom (SA)- and monolayer (ML)-supported catalysts are two main technical routines to increase electrochemical catalytic performance and reduce cost. To date, it is still a debate which one is better for catalysis in experiments as both routines face a puzzling problem of searching for balance between stability and catalytic activity. Here, hydrogen evolution on two-dimensional 2H-MoS2 with SA- and ML-adsorbed metal atoms (23 kinds in total) is taken as an example to solve this question by first-principles calculations. The thermodynamic stability during synthesis, in vacuum, and in electrochemical reaction conditions is determined to access the stability of MoS2 loaded with single (MS@MoS2) and monolayer metal atoms (MM@MoS2). The realistic catalytic surfaces determined by surface Pourbaix diagrams, the free energy changes of hydrogen atoms at different coverages, and the exchange current densities are applied to determine hydrogen evolution reaction (HER) activity. The results show that all MM@MoS2 are much more stable than the corresponding MS@MoS2 as the metal-metal interaction in MLs could make the former structures more stable. In general, MM@MoS2 show higher hydrogen evolution activities than those of MS@MoS2. In detail, the exchange current densities of MoS2 loaded by Pd ML and Au ML are 6.208, and 1.109 mA/cm-2, respectively, which are comparable to Pt(111). Combining with small binding energies, the Pd and Au MLs are the most promising catalysts for hydrogen evolution. The purpose of this work is to highlight the advantages and disadvantages of SA- and ML-supported surfaces as HER catalysts and provide a fundamental standard for studying them.
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Affiliation(s)
- Ya-Nan Zhu
- Guangzhou Key Laboratory for New Energy and Green Catalysis, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China
| | - Xi-Bo Li
- Department of Physics, Jinan University, Guangzhou 510632, China
| | - Qiao Zhang
- Guangzhou Key Laboratory for New Energy and Green Catalysis, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China
| | - Feng Peng
- Guangzhou Key Laboratory for New Energy and Green Catalysis, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China
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11
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Liu N, Zhou S, Zhao J. Photoinduced Spin Injection and Ferromagnetism in 2D Group III Monochalcogenides. J Phys Chem Lett 2022; 13:590-597. [PMID: 35015540 DOI: 10.1021/acs.jpclett.1c03994] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Strong light-matter interactions in low-dimensional materials offer an opportunity for flexible property-tuning by optical switching. Herein, we exploit photoexcitation for spin injection into semiconductors by rationally designing heterojunctions having distinct dynamic behavior for photocarriers in two spin channels. As a proof-of-concept, we trigger homogeneous magnetism in a group III monochalcogenide monolayer (MX with M = In, Ga; X = S, Se) by placing it on a ferromagnetic CrI3 substrate under light illumination. Our time-dependent ab initio nonadiabatic molecular dynamics simulations reveal fast electron-hole separation for the majority spin channel but rapid recombination for the minority spin channel at this heterostructure. The majority carriers cause hole doping and strong ferromagnetic ordering in the MX sheet, with magnetic moment tunable by the injected carriers' concentration. The interplay between photoexcited hole carriers, the Van Hove singularity of MX monolayers, and interfacial charge transfer provides essential physical insights for nondestructively manipulating charge and spin in two-dimensional semiconductors via light switching.
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Affiliation(s)
- Nanshu Liu
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024, China
- Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices, Department of Physics, Renmin University of China, Beijing 100872, P.R. China
| | - Si Zhou
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024, China
| | - Jijun Zhao
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024, China
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12
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Li D, Li S, Zhong C, He J. Tuning magnetism at the two-dimensional limit: a theoretical perspective. NANOSCALE 2021; 13:19812-19827. [PMID: 34825688 DOI: 10.1039/d1nr06835k] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The discovery of two-dimensional (2D) magnetic materials provides an ideal testbed for manipulating the magnetic properties at the atomically thin and 2D limit. This review gives recent progress in the emergent 2D magnets and heterostructures, focusing on the theory side. We summarize different theoretical models, ranging from the atomic to micrometer-scale, used to describe magnetic orders. Then, the current strategies for tuning magnetism in 2D materials are further discussed, such as electric field, magnetic field, strain, optics, chemical functionalization, and spin-orbit engineering. Finally, we conclude with the future challenges and opportunities for 2D magnetism.
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Affiliation(s)
- Dongzhe Li
- Institute for Advanced Study, Chengdu University, Chengdu 610100, P. R. China.
| | - Shuo Li
- Institute for Advanced Study, Chengdu University, Chengdu 610100, P. R. China.
| | - Chengyong Zhong
- Institute for Advanced Study, Chengdu University, Chengdu 610100, P. R. China.
| | - Junjie He
- Bremen Center for Computational Materials Science, University of Bremen, Am Fallturm 1, 2835, Bremen, Germany
- Department of Physical and Macromolecular Chemistry & Charles University Centre of Advanced Materials, Faculty of Science, Charles University in Prague, Hlavova 8, Prague 2, 128 43, Czech Republic.
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13
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Joseph T, Ghorbani-Asl M, Batzill M, Krasheninnikov AV. Water dissociation and association on mirror twin boundaries in two-dimensional MoSe 2: insights from density functional theory calculations. NANOSCALE ADVANCES 2021; 3:6992-7001. [PMID: 36132369 PMCID: PMC9419107 DOI: 10.1039/d1na00429h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 10/21/2021] [Indexed: 06/07/2023]
Abstract
The adsorption and dissociation of water molecules on two-dimensional transition metal dichalcogenides (TMDs) is expected to be dominated by point defects, such as vacancies, and edges. At the same time, the role of grain boundaries, and particularly, mirror twinboundaries (MTBs), whose concentration in TMDs can be quite high, is not fully understood. Using density functional theory calculations, we investigate the interaction of water, hydroxyl groups, as well as oxygen and hydrogen molecules with MoSe2 monolayers when MTBs of various types are present. We show that the adsorption of all species on MTBs is energetically favorable as compared to that on the basal plane of pristine MoSe2, but the interaction with Se vacancies is stronger. We further assess the energetics of various surface chemical reactions involving oxygen and hydrogen atoms. Our results indicate that water dissociation on the basal plane should be dominated by vacancies even when MTBs are present, but they facilitate water clustering through hydroxyl groups at MTBs, which can anchor water molecules and give rise to the decoration of MTBs with water clusters. Also, the presence of MTBs affects oxygen reduction reaction (ORR) on the MoSe2 monolayer. Unlike Se vacancies which inhibit ORR due to a high overpotential, it is found that the ORR process on MTBs is more efficient, indicating their important role in the catalytic activity of MoSe2 monolayer and likely other TMDs.
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Affiliation(s)
- T Joseph
- Institute of Ion Beam Physics and Materials Research Helmholtz-Zentrum Dresden-Rossendorf 01328 Dresden Germany
| | - M Ghorbani-Asl
- Department of Physics, University of South Florida Tampa FL 33620 USA
| | - M Batzill
- Department of Applied Physics, Aalto University P.O. Box 11100 00076 Aalto Finland
| | - Arkady V Krasheninnikov
- Institute of Ion Beam Physics and Materials Research Helmholtz-Zentrum Dresden-Rossendorf 01328 Dresden Germany
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14
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Jayan R, Islam MM. Design Principles of Bifunctional Electrocatalysts for Engineered Interfaces in Na–S Batteries. ACS Catal 2021. [DOI: 10.1021/acscatal.1c04739] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Rahul Jayan
- Department of Mechanical Engineering, Wayne State University, Detroit, Michigan 48202, United States
| | - Md Mahbubul Islam
- Department of Mechanical Engineering, Wayne State University, Detroit, Michigan 48202, United States
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15
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Fonseca HAB, Verga LG, Da Silva JLF. Ab Initio Study of CO 2 Activation on Pristine and Fe-Decorated WS 2 Nanoflakes. J Phys Chem A 2021; 125:7769-7777. [PMID: 34472858 DOI: 10.1021/acs.jpca.1c04436] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
There is an intense race by the scientific community to identify materials with potential applications for the conversion of carbon dioxide (CO2) into new products. To extend the range of possibilities and explore new effects, in this work, we employ density functional theory calculations to investigate the presence of edge effects in the adsorption and activation of CO2 on pristine and Fe-decorated (WS2)16 nanoflakes. We found that Fe has an energetic preference for hollow sites on pristine nanoflakes, binding with at least two two-fold edge S atoms and one or two three-fold core S atoms. Fe adsorption on the bridge sites occurs only at the edges, which is accompanied by the breaking of W-S bonds in most cases (higher energy configurations). CO2 activates on (WS2)16 with an OCO angle of about 129° only at higher energy configurations, while CO2 binds via a physisorption mechanism, linear structure, in the lowest energy configuration. For CO2 on Fe/(WS2)16, the activation occurs at lower energies only by the direct interaction of CO2 with Fe sites located near to the nanoflake edges, which clearly indicates the enhancement of the catalytic activity of (WS2)16 nanoflakes by Fe decoration. Thus, our study indicates that decorating WS2 nanoflakes with TM atoms could be an interesting strategy to explore alternative catalysts based on two-dimensional materials.
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Affiliation(s)
- Henrique A B Fonseca
- São Carlos Institute of Chemistry, University of São Paulo, P.O. Box 780, 13560-970 São Carlos, SP, Brazil
| | - Lucas G Verga
- São Carlos Institute of Chemistry, University of São Paulo, P.O. Box 780, 13560-970 São Carlos, SP, Brazil
| | - Juarez L F Da Silva
- São Carlos Institute of Chemistry, University of São Paulo, P.O. Box 780, 13560-970 São Carlos, SP, Brazil
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16
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Liu L, Hu X, Wang Y, Krasheninnikov AV, Chen Z, Sun L. Tunable electronic properties and enhanced ferromagnetism in Cr 2Ge 2Te 6monolayer by strain engineering. NANOTECHNOLOGY 2021; 32:485408. [PMID: 34348248 DOI: 10.1088/1361-6528/ac1a94] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 08/04/2021] [Indexed: 06/13/2023]
Abstract
Recently, as a new representative of Heisenberg's two-dimensional (2D) ferromagnetic materials, 2D Cr2Ge2Te6(CGT), has attracted much attention due to its intrinsic ferromagnetism. Unfortunately, the Curie temperature (TC) of CGT monolayer is only 22 K, which greatly hampers the development of the applications based on the CGT materials. Herein, by means of density functional theory computations, we explored the electronic and magnetic properties of CGT monolayer under the applied strain. It is demonstrated that the band gap of CGT monolayer can be remarkably modulated by applying the tensile strain, which first increases and then decreases with the increase of tensile strain. In addition, the strain can increase the Curie temperature and magnetic moment, and thus largely enhance the ferromagnetism of CGT monolayer. Notably, the obvious enhancement ofTCby 191% can be achieved at 10% strain. These results demonstrate that strain engineering can not only tune the electronic properties, but also provide a promising avenue to improve the ferromagnetism of CGT monolayer. The remarkable electronic and magnetic response to biaxial strain can also facilitate the development of CGT-based spin devices.
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Affiliation(s)
- Lifei Liu
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China
| | - Xiaohui Hu
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 211816, People's Republic of China
| | - Yifeng Wang
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 211816, People's Republic of China
| | - Arkady V Krasheninnikov
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, D-01314 Dresden, Germany
- Department of Applied Physics, Aalto University School of Science, PO Box 11100, FI-00076 Aalto, Finland
| | - Zhongfang Chen
- Department of Chemistry, University of Puerto Rico, Rio Piedras Campus, San Juan, PR 00931 United States of America
| | - Litao Sun
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, Collaborative Innovation Center for Micro/Nano Fabrication, Device and System, Southeast University, Nanjing 210096, People's Republic of China
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17
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Kim D, Ren Y, Cui M, Lee Y, Kim J, Kwon O, Ji W, Khim J. Arsenic adsorption on two types of powdered and beaded coal mine drainage sludge adsorbent. CHEMOSPHERE 2021; 272:129560. [PMID: 33460828 DOI: 10.1016/j.chemosphere.2021.129560] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/03/2021] [Accepted: 01/04/2021] [Indexed: 06/12/2023]
Abstract
The aim of this study was to evaluate the performance of a new adsorbent in terms of beading the sludge generated from coal mine drainage or arsenic removed from water is treated by electro-purification (EP) and chemical-precipitation (CP) methods. Batch experiments were conducted to study the influence of experimental parameters such as pH and temperature, as well as the mechanism of arsenic adsorption with the new adsorbent. The porosity of coal mine drainage sludge (CMDS)-beaded adsorbent made of chitosan and alginate was optimized by adding NaHCO3 powder to generate CO2 gas during the preparation process. Two types of adsorbents, beaded EP Najeon CMDS (BCMDSEP-NJ) and beaded CP Yeongdong CMDS (BCMDSCP-YD), were prepared by heating. The specific surface areas of the powdered adsorbents CMDSEP-NJ and CMDSCP-YD were 104 and 231 m2 g-1, respectively. The prepared beaded adsorbents BCMDSEP-NJ and BCMDSCP-YD had good porosity and specific surface areas of 16.8 and 21.2 m2 g-1, respectively. The X-ray diffraction results showed that the structure was goethite (aragonite) and schwertmannite. The pseudo second-order, intra-particle, and Langmuir models were used to explain the adsorption process. The qmax values of As(III) with BCDMSEP-NJ and BCMDSCP-YD adsorbents are 4.31 and 4.58 mg g-1, respectively and those of AS(V) are 9.31 and 10.93 mg g-1, respectively. The adsorption capacity for As(III) increased with increasing pH, whereas that for As(V) decreased. The activation energy was 8 kJ mol-1 or more. The mechanism of adsorption of arsenic using a beaded adsorbent was chemical adsorption followed by diffusion. The results of the present study suggest that new adsorbents can be effectively utilized for arsenic removal from water.
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Affiliation(s)
- Dongik Kim
- School of Civil, Environmental, and Architectural Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Yangmin Ren
- School of Civil, Environmental, and Architectural Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Mingcan Cui
- School of Civil, Environmental, and Architectural Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea.
| | - Yonghyeon Lee
- School of Civil, Environmental, and Architectural Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Jeonggwan Kim
- Korea Environmental Industry and Technology, 215 Jinheung-no, Eunpyeong-gu, Seoul, 03367, Republic of Korea
| | - Ohhun Kwon
- Mine Reclamation Corporation, 2, Segye-ro, Wonju-si, Gangwon-do, 26464, Republic of Korea
| | - Wonhyun Ji
- Mine Reclamation Corporation, 2, Segye-ro, Wonju-si, Gangwon-do, 26464, Republic of Korea
| | - Jeehyeong Khim
- School of Civil, Environmental, and Architectural Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea.
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18
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Yang Q, Hu X, Shen X, Krasheninnikov AV, Chen Z, Sun L. Enhancing Ferromagnetism and Tuning Electronic Properties of CrI 3 Monolayers by Adsorption of Transition-Metal Atoms. ACS APPLIED MATERIALS & INTERFACES 2021; 13:21593-21601. [PMID: 33904708 DOI: 10.1021/acsami.1c01701] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Among first experimentally discovered two-dimensional (2D) ferromagnetic materials, chromium triiodide (CrI3) monolayers have attracted particular attention due to their potential applications in electronics and spintronics. However, the Curie temperature Tc of the CrI3 monolayer is below room temperature, which greatly limits practical development of the devices. Herein, using density functional theory calculation, we explore how the electronic and magnetic properties of CrI3 monolayers change upon adsorption of 3d transition-metal (TM) atoms (from Sc to Zn). Our results indicate that the electronic properties of the TM-CrI3 system can be tuned from semiconductor to metal/half-metal/spin gapless semiconductor depending on the choice of the adsorbed TM atoms. Moreover, the adsorption can improve the ferromagnetic stability of CrI3 monolayers by increasing both magnetic moments and Tc. Notably, Tc of CrI3 with Sc and V adatoms can be increased by nearly a factor of 3. We suggest postsynthesis doping of 2D CrI3 by deposition of TM atoms as a new route toward potential applications of TM-CrI3 systems in nanoelectronic and spintronic devices.
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Affiliation(s)
- Qiang Yang
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Xiaohui Hu
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 211816, China
| | - Xiaodong Shen
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 211816, China
| | - Arkady V Krasheninnikov
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden, Germany
- Department of Applied Physics, Aalto University School of Science, P.O. Box 11100, 00076 Aalto, Finland
| | - Zhongfang Chen
- Department of Chemistry, University of Puerto Rico, Rio Piedras Campus, San Juan 00931, Puerto Rico
| | - Litao Sun
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, Collaborative Innovation Center for Micro/Nano Fabrication, Device and System, Southeast University, Nanjing 210096, China
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19
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Lin Y, Torsi R, Geohegan DB, Robinson JA, Xiao K. Controllable Thin-Film Approaches for Doping and Alloying Transition Metal Dichalcogenides Monolayers. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2004249. [PMID: 33977064 PMCID: PMC8097379 DOI: 10.1002/advs.202004249] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 12/06/2020] [Indexed: 06/01/2023]
Abstract
Two-dimensional (2D) transition metal dichalcogenides (TMDs) exhibit exciting properties and versatile material chemistry that are promising for device miniaturization, energy, quantum information science, and optoelectronics. Their outstanding structural stability permits the introduction of various foreign dopants that can modulate their optical and electronic properties and induce phase transitions, thereby adding new functionalities such as magnetism, ferroelectricity, and quantum states. To accelerate their technological readiness, it is essential to develop controllable synthesis and processing techniques to precisely engineer the compositions and phases of 2D TMDs. While most reviews emphasize properties and applications of doped TMDs, here, recent progress on thin-film synthesis and processing techniques that show excellent controllability for substitutional doping of 2D TMDs are reported. These techniques are categorized into bottom-up methods that grow doped samples on substrates directly and top-down methods that use energetic sources to implant dopants into existing 2D crystals. The doped and alloyed variants from Group VI TMDs will be at the center of technical discussions, as they are expected to play essential roles in next-generation optoelectronic applications. Theoretical backgrounds based on first principles calculations will precede the technical discussions to help the reader understand each element's likelihood of substitutional doping and the expected impact on the material properties.
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Affiliation(s)
- Yu‐Chuan Lin
- Department of Materials Science and EngineeringThe Pennsylvania State UniversityUniversity ParkPA16802USA
| | - Riccardo Torsi
- Department of Materials Science and EngineeringThe Pennsylvania State UniversityUniversity ParkPA16802USA
| | - David B. Geohegan
- Center for Nanophase Materials SciencesOak Ridge National LaboratoryOak RidgeTN37831USA
| | - Joshua A. Robinson
- Department of Materials Science and EngineeringThe Pennsylvania State UniversityUniversity ParkPA16802USA
- Two‐Dimensional Crystal ConsortiumThe Pennsylvania State UniversityUniversity ParkPA16802USA
- Center for 2‐Dimensional and Layered MaterialsThe Pennsylvania State UniversityUniversity ParkPA16802USA
| | - Kai Xiao
- Center for Nanophase Materials SciencesOak Ridge National LaboratoryOak RidgeTN37831USA
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20
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Siao MD, Lin YC, He T, Tsai MY, Lee KY, Chang SY, Lin KI, Lin YF, Chou MY, Suenaga K, Chiu PW. Embedment of Multiple Transition Metal Impurities into WS 2 Monolayer for Bandstructure Modulation. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2007171. [PMID: 33711202 DOI: 10.1002/smll.202007171] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 02/12/2021] [Indexed: 06/12/2023]
Abstract
Band structure by design in 2D layered semiconductors is highly desirable, with the goal to acquire the electronic properties of interest through the engineering of chemical composition, structure, defect, stacking, or doping. For atomically thin transition metal dichalcogenides, substitutional doping with more than one single type of transition metals is the task for which no feasible approach is proposed. Here, the growth of WS2 monolayer is shown codoped with multiple kinds of transition metal impurities via chemical vapor deposition controlled in a diffusion-limited mode. Multielement embedment of Cr, Fe, Nb, and Mo into the host lattice is exemplified. Abundant impurity states thus generate in the bandgap of the resultant WS2 and provide a robust switch of charging/discharging states upon sweep of an electric filed. A profound memory window exists in the transfer curves of doped WS2 field-effect transistors, forming the basis of binary states for robust nonvolatile memory. The doping technique presented in this work brings one step closer to the rational design of 2D semiconductors with desired electronic properties.
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Affiliation(s)
- Ming-Deng Siao
- Department of Electrical Engineering, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Yung-Chang Lin
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, 305-8565, Japan
| | - Tao He
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
| | - Meng-Yu Tsai
- Department of Electrical Engineering, National Tsing Hua University, Hsinchu, 30013, Taiwan
- Department of Physics, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Kuei-Yi Lee
- Graduate Institute of Electro-Optical Engineering, National Taiwan University of Science and Technology, Taipei, 10607, Taiwan
| | - Shou-Yi Chang
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Kuang-I Lin
- Center for Micro/Nano Science and Technology, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Yen-Fu Lin
- Department of Physics, National Chung Hsing University, Taichung, 40227, Taiwan
| | - Mei-Yin Chou
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
- Department of Physics, National Taiwan University, Taipei, 10617, Taiwan
| | - Kazu Suenaga
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, 305-8565, Japan
| | - Po-Wen Chiu
- Department of Electrical Engineering, National Tsing Hua University, Hsinchu, 30013, Taiwan
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan
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21
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Lin YC, Karthikeyan J, Chang YP, Li S, Kretschmer S, Komsa HP, Chiu PW, Krasheninnikov AV, Suenaga K. Formation of Highly Doped Nanostripes in 2D Transition Metal Dichalcogenides via a Dislocation Climb Mechanism. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2007819. [PMID: 33604926 DOI: 10.1002/adma.202007819] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/21/2020] [Indexed: 06/12/2023]
Abstract
Doping of materials beyond the dopant solubility limit remains a challenge, especially when spatially nonuniform doping is required. In 2D materials with a high surface-to-volume ratio, such as transition metal dichalcogenides, various post-synthesis approaches to doping have been demonstrated, but full control over spatial distribution of dopants remains a challenge. A post-growth doping of single layers of WSe2 is performed by adding transition metal (TM) atoms in a two-step process, which includes annealing followed by deposition of dopants together with Se or S. The Ti, V, Cr, and Fe impurities at W sites are identified by using transmission electron microscopy and electron energy loss spectroscopy. Remarkably, an extremely high density (6.4-15%) of various types of impurity atoms is achieved. The dopants are revealed to be largely confined within nanostripes embedded in the otherwise pristine WSe2 . Density functional theory calculations show that the dislocations assist the incorporation of the dopant during their climb and give rise to stripes of TM dopant atoms. This work demonstrates a possible spatially controllable doping strategy to achieve the desired local electronic, magnetic, and optical properties in 2D materials.
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Affiliation(s)
- Yung-Chang Lin
- Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, 305-8565, Japan
| | - Jeyakumar Karthikeyan
- Department of Applied Physics, Aalto University, P. O. Box 11100, Aalto, 00076, Finland
- Department of Basic Sciences and Humanities, Rajiv Gandhi Institute of Petroleum Technology, Jais, Amethi, Uttar Pradesh, 229304, India
| | - Yao-Pang Chang
- Department of Electrical Engineering, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Shisheng Li
- International Center for Young Scientists (ICYS), National Institute for Materials Science (NIMS), Tsukuba, 305-0044, Japan
| | - Silvan Kretschmer
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - Hannu-Pekka Komsa
- Department of Applied Physics, Aalto University, P. O. Box 11100, Aalto, 00076, Finland
- Microelectronics Research Unit, University of Oulu, P. O. Box 8000, Oulu, 90014, Finland
| | - Po-Wen Chiu
- Department of Electrical Engineering, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Arkady V Krasheninnikov
- Department of Applied Physics, Aalto University, P. O. Box 11100, Aalto, 00076, Finland
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - Kazu Suenaga
- Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, 305-8565, Japan
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22
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Sukhanova EV, Kvashnin DG, Popov ZI. Induced spin polarization in graphene via interactions with halogen doped MoS 2 and MoSe 2 monolayers by DFT calculations. NANOSCALE 2020; 12:23248-23258. [PMID: 33206100 DOI: 10.1039/d0nr06287a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Magnetic halogen doped MoX2 (X = S and Se) monolayers influenced the electronic structure of graphene through a proximity effect. This process was observed using state-of-the-art calculations. It was found that the substitution of a single chalcogen atom with a halogen atom (F, Cl, Br, and I) results in n-type doping of MoX2. An additional electron from the dopant is localized on binding orbitals with the nearest Mo atoms and leads to the formation of magnetism in the dichalcogenide layer. Detailed analysis of halogen doped MoX2/graphene heterostructures demonstrated the induction of spin polarization in graphene near the Fermi energy. Significant spin polarization near the Fermi energy and n-type doping were observed in the graphene layer of MoSe2/graphene heterostructures with MoSe2 doped with iodine. At the same time, fluorine-doped MoSe2 does not cause n-doping in graphene, while spin polarization still takes place. The possibility for the detection of the arrangement of the halogen impurities at the MoX2 basal plane even with the graphene layer deposited on top was demonstrated through STM measurements which will be undoubtedly useful for the fabrication of electronic schemes and elements based on the proposed heterostructures for their further application in nanoelectronics and spintronics.
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Affiliation(s)
- Ekaterina V Sukhanova
- Moscow Institute of Physics and Technology (State University), 9 Institutskiy per., Dolgoprudny, Moscow Region, 141701, Russian Federation.
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23
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Chen S, Johnson VL, Donadio D, Koski KJ. Mn-intercalated MoSe 2 under pressure: Electronic structure and vibrational characterization of a dilute magnetic semiconductor. J Chem Phys 2020; 153:124701. [PMID: 33003721 DOI: 10.1063/5.0018716] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Intercalation offers a promising way to alter the physical properties of two-dimensional (2D) layered materials. Here, we investigate the electronic and vibrational properties of 2D layered MoSe2 intercalated with atomic manganese at ambient and high pressure up to 7 GPa by Raman scattering and electronic structure calculations. The behavior of optical phonons is studied experimentally with a diamond anvil cell and computationally through density functional theory calculations. Experiment and theory show excellent agreement in optical phonon behavior. The previously Raman inactive A2u mode is activated and enhanced with intercalation and pressure, and a new Raman mode appears upon decompression, indicating a possible onset of a localized structural transition, involving the bonding or trapping of the intercalant in 2D layered materials. Density functional theory calculations reveal a shift of the Fermi level into the conduction band and spin polarization in MnxMoSe2 that increases at low Mn concentrations and low pressure. Our results suggest that intercalation and pressurization of van der Waals materials may allow one to obtain dilute magnetic semiconductors with controllable properties, providing a viable route for the development of new materials for spintronic applications.
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Affiliation(s)
- Shunda Chen
- Department of Chemistry, University of California Davis, One Shields Ave., Davis, California 95616, USA
| | - Virginia L Johnson
- Department of Chemistry, University of California Davis, One Shields Ave., Davis, California 95616, USA
| | - Davide Donadio
- Department of Chemistry, University of California Davis, One Shields Ave., Davis, California 95616, USA
| | - Kristie J Koski
- Department of Chemistry, University of California Davis, One Shields Ave., Davis, California 95616, USA
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Yang Q, Kou L, Hu X, Wang Y, Lu C, Krasheninnikov AV, Sun L. Strain robust spin gapless semiconductors/half-metals in transition metal embedded MoSe 2monolayer. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:365305. [PMID: 32369800 DOI: 10.1088/1361-648x/ab9052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 05/05/2020] [Indexed: 06/11/2023]
Abstract
The realization of spin gapless semiconductor (SGS) and half-metal (HM) behavior in two-dimensional (2D) transition metal (TM) dichalcogenides is highly desirable for their applications in spintronic devices. Here, using density functional theory calculations, we demonstrate that Fe, Co, Ni substitutional impurities can not only induce magnetism in MoSe2monolayer, but also convert the semiconducting MoSe2to SGS/HM system. We also study the effects of mechanical strain on the electronic and magnetic properties of the doped monolayer. We show that for all TM impurities we considered, the system exhibits the robust SGS/HM behavior regardless of biaxial strain values. Moreover, it is found that the magnetic properties of TM-MoSe2can effectively be tuned under biaxial strain by controlling the spin polarization of the 3dorbitals of Fe, Co, Ni atoms. Our findings offer a new route to designing the SGS/HM properties and modulating magnetic characteristics of the TM-MoSe2system and may also facilitate the implementation of SGS/HM behavior and realization of spintronic devices based on other 2D materials.
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Affiliation(s)
- Qiang Yang
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China
| | - Liangzhi Kou
- School of Chemistry, Physics and Mechanical Engineering Faculty, Queensland University of Technology, Garden Point Campus, Brisbane, QLD 4001, Australia
| | - Xiaohui Hu
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 211816, People's Republic of China
| | - Yifeng Wang
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 211816, People's Republic of China
| | - Chunhua Lu
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 211816, People's Republic of China
| | - Arkady V Krasheninnikov
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden, Germany
- Department of Applied Physics, Aalto University School of Science, PO Box 11100, 00076 Aalto, Finland
| | - Litao Sun
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, Collaborative Innovation Center for Micro/Nano Fabrication, Device and System, Southeast University, Nanjing 210096, People's Republic of China
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Hu X, Zhao Y, Shen X, Krasheninnikov AV, Chen Z, Sun L. Enhanced Ferromagnetism and Tunable Magnetism in Fe 3GeTe 2 Monolayer by Strain Engineering. ACS APPLIED MATERIALS & INTERFACES 2020; 12:26367-26373. [PMID: 32408732 DOI: 10.1021/acsami.0c05530] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Recent discovery of intrinsic ferromagnetism in Fe3GeTe2 (FGT) monolayer [Deng, Y.; Nature 2018, 563, 94-99; Fei, Z.; Nat. Mater. 2018, 17, 778-782] not only extended the family of two-dimensional (2D) magnetic materials but also stimulated further interest in the possibility to tune their magnetic properties without changing the chemical composition or introducing defects. By means of density functional theory computations, we explore strain effects on the magnetic properties of the FGT monolayer. We demonstrate that the ferromagnetism can be largely enhanced by the tensile strain in the FGT monolayer due to the competitive effects of direct exchange and superexchange interaction. The average magnetic moments of Fe atoms increase monotonically with an increase in biaxial strain from -5 to 5% in FGT monolayer. The intriguing variation of magnetic moments with strain in the FGT monolayer is related to the charge transfer induced by the changes in the bond lengths. Given the successful fabrication of the FGT monolayer, the strain-tunable ferromagnetism in the FGT monolayer can stimulate the experimental effort in this field. This work also suggests an effective route to control the magnetic properties of the FGT monolayer. The pronounced magnetic response toward the biaxial strain can be used to design the magnetomechanical coupling spintronics devices based on FGT.
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Affiliation(s)
- Xiaohui Hu
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 211816, China
| | - Yinghe Zhao
- Department of Chemistry, University of Puerto Rico, Rio Piedras Campus, San Juan 00931, Puerto Rico
| | - Xiaodong Shen
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, China
- Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 211816, China
| | - Arkady V Krasheninnikov
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden, Germany
- Department of Applied Physics, Aalto University School of Science, PO Box 11100, 00076 Aalto, Finland
| | - Zhongfang Chen
- Department of Chemistry, University of Puerto Rico, Rio Piedras Campus, San Juan 00931, Puerto Rico
| | - Litao Sun
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, Collaborative Innovation Center for Micro/Nano Fabrication, Device and System, Southeast University, Nanjing 210096, China
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26
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Engineering covalently bonded 2D layered materials by self-intercalation. Nature 2020; 581:171-177. [DOI: 10.1038/s41586-020-2241-9] [Citation(s) in RCA: 97] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Accepted: 03/04/2020] [Indexed: 11/08/2022]
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Zhang K, Pan Y, Wang L, Mei WN, Wu X. Extended 1D defect induced magnetism in 2D MoS 2 crystal. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:215302. [PMID: 32032012 DOI: 10.1088/1361-648x/ab73a3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Exploring two dimensional (2D) magnetic materials is important for both fundamental research and practical applications in nanoscale spintronics. Although dispersive doping of atoms in 2D nonmagnetic transition-metal dichalcogenides (TMD) has been broadly studied in recent years, the regular linear substitution inside 2D nonmagnetic TMD is rarely explored. Herein, based on first-principles calculations, we report a series of hybrid magnetic structures formed by linear atomic doping in MoS2 monolayer. We demonstrate that F and Fe atoms linear-doped MoS2 are ferromagnetic semi-metals while Mn and Co atoms linear-doped MoS2 are ferromagnetic semiconductors in their ground states. Except for F dopant, the magnetic ground states of Mn, Fe, or Co atom linear-doped MoS2 are independent of the width of linear defect. The thermal and lattice dynamical stabilities of linear-doped MoS2 monolayer are confirmed with the molecular dynamics simulations and phonon spectra. A ferromagnetic semi-metal or semiconductor to half-metallic ferromagnet transition in doped MoS2 monolayer is revealed with applying strain. Further, atomically thin magnetic zones with different shapes can also be achieved by arranging the dopants. The induced magnetic properties render linear-doped MoS2 a promising material for spintronics in the nanoscale.
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Affiliation(s)
- Kai Zhang
- School of Chemistry and Materials Science, CAS Key Laboratory of Materials for Energy Conversion, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
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28
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Meza E, Diaz RE, Li CW. Solution-Phase Activation and Functionalization of Colloidal WS 2 Nanosheets with Ni Single Atoms. ACS NANO 2020; 14:2238-2247. [PMID: 31994865 DOI: 10.1021/acsnano.9b09245] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Single-atom functionalization of transition-metal dichalcogenide (TMD) nanosheets is a powerful strategy to tune the optical, magnetic, and catalytic properties of two-dimensional materials. In this work, we demonstrate a simple solution-phase method to generate nucleophilic sulfide sites on colloidal WS2 nanosheets that subsequently serve as ligands for Ni single atoms. These materials can be controllably functionalized with varying amounts of Ni on the surface ranging from 9% to 47% coverage with respect to W. High-resolution scanning transmission electron microscopy coupled to electron energy loss spectroscopy and X-ray absorption spectroscopy indicate that adsorbed Ni species bind as single atoms at low coverage and a mixture of single atoms and multimetallic clusters at high coverage. The Ni single atoms adsorbed on WS2 show altered electronic properties, and both the electronic perturbation and isolated atom geometry play a role in enhancing the intrinsic catalytic activity of Ni-WS2 samples for the electrochemical oxygen evolution reaction.
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Affiliation(s)
- Erika Meza
- Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States
| | - Rosa E Diaz
- Birck Nanotechnology Center , Purdue University , West Lafayette , Indiana 47907 , United States
| | - Christina W Li
- Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States
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Schuler B, Lee JH, Kastl C, Cochrane KA, Chen CT, Refaely-Abramson S, Yuan S, van Veen E, Roldán R, Borys NJ, Koch RJ, Aloni S, Schwartzberg AM, Ogletree DF, Neaton JB, Weber-Bargioni A. How Substitutional Point Defects in Two-Dimensional WS 2 Induce Charge Localization, Spin-Orbit Splitting, and Strain. ACS NANO 2019; 13:10520-10534. [PMID: 31393700 DOI: 10.1021/acsnano.9b04611] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Control of impurity concentrations in semiconducting materials is essential to device technology. Because of their intrinsic confinement, the properties of two-dimensional semiconductors such as transition metal dichalcogenides (TMDs) are more sensitive to defects than traditional bulk materials. The technological adoption of TMDs is dependent on the mitigation of deleterious defects and guided incorporation of functional foreign atoms. The first step toward impurity control is the identification of defects and assessment of their electronic properties. Here, we present a comprehensive study of point defects in monolayer tungsten disulfide (WS2) grown by chemical vapor deposition using scanning tunneling microscopy/spectroscopy, CO-tip noncontact atomic force microscopy, Kelvin probe force spectroscopy, density functional theory, and tight-binding calculations. We observe four different substitutional defects: chromium (CrW) and molybdenum (MoW) at a tungsten site, oxygen at sulfur sites in both top and bottom layers (OS top/bottom), and two negatively charged defects (CD type I and CD type II). Their electronic fingerprints unambiguously corroborate the defect assignment and reveal the presence or absence of in-gap defect states. CrW forms three deep unoccupied defect states, two of which arise from spin-orbit splitting. The formation of such localized trap states for CrW differs from the MoW case and can be explained by their different d shell energetics and local strain, which we directly measured. Utilizing a tight-binding model the electronic spectra of the isolectronic substitutions OS and CrW are mimicked in the limit of a zero hopping term and infinite on-site energy at a S and W site, respectively. The abundant CDs are negatively charged, which leads to a significant band bending around the defect and a local increase of the contact potential difference. In addition, CD-rich domains larger than 100 nm are observed, causing a work function increase of 1.1 V. While most defects are electronically isolated, we also observed hybrid states formed between CrW dimers. The important role of charge localization, spin-orbit coupling, and strain for the formation of deep defect states observed at substitutional defects in WS2 as reported here will guide future efforts of targeted defect engineering and doping of TMDs.
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Affiliation(s)
- Bruno Schuler
- Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Jun-Ho Lee
- Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
- Department of Physics , University of California at Berkeley , Berkeley , California 94720 , United States
| | - Christoph Kastl
- Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
- Walter-Schottky-Institut and Physik-Department , Technical University of Munich , Garching 85748 , Germany
| | - Katherine A Cochrane
- Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Christopher T Chen
- Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Sivan Refaely-Abramson
- Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 7610001 , Israel
| | - Shengjun Yuan
- Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology , Wuhan University , Wuhan 430072 , China
| | - Edo van Veen
- Radboud University of Nijmegen , Institute for Molecules and Materials , Heijendaalseweg 135 , 6525 AJ , Nijmegen , The Netherlands
| | - Rafael Roldán
- Instituto de Ciencia de Materiales de Madrid , ICMM-CSIC, Cantoblanco, E-28049 , Madrid , Spain
| | - Nicholas J Borys
- Department of Physics , Montana State University , Bozeman , Montana 59717 , United States
| | - Roland J Koch
- Advanced Light Source , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Shaul Aloni
- Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Adam M Schwartzberg
- Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - D Frank Ogletree
- Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Jeffrey B Neaton
- Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
- Department of Physics , University of California at Berkeley , Berkeley , California 94720 , United States
- Kavli Energy Nanosciences Institute at Berkeley , Berkeley , California 94720 , United States
| | - Alexander Weber-Bargioni
- Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
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30
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Sun J, Peng M, Zhang Y, Zhang L, Peng R, Miao C, Liu D, Han M, Feng R, Ma Y, Dai Y, He L, Shan C, Pan A, Hu W, Yang ZX. Ultrahigh Hole Mobility of Sn-Catalyzed GaSb Nanowires for High Speed Infrared Photodetectors. NANO LETTERS 2019; 19:5920-5929. [PMID: 31374165 DOI: 10.1021/acs.nanolett.9b01503] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Owing to the relatively low hole mobility, the development of GaSb nanowire (NW) electronic and photoelectronic devices has stagnated in the past decade. During a typical catalyst-assisted chemical vapor deposition (CVD) process, the adopted metallic catalyst can be incorporated into the NW body to act as a slight dopant, thus regulating the electrical properties of the NW. In this work, we demonstrate the use of Sn as a catalyst and dopant for GaSb NWs in the surfactant-assisted CVD growth process. The Sn-catalyzed zinc-blende GaSb NWs are thin, long, and straight with good crystallinity, resulting in a record peak hole mobility of 1028 cm2 V-1 s-1. This high mobility is attributed to the slight doping of Sn atoms from the catalyst tip into the NW body, which is verified by the red-shifted photoluminescence peak of Sn-catalyzed GaSb NWs (0.69 eV) compared with that of Au-catalyzed NWs (0.74 eV). Furthermore, the parallel array NWs also show a high peak hole mobility of 170 cm2 V-1 s-1, a high responsivity of 61 A W-1, and fast rise and decay times of 195.1 and 380.4 μs, respectively, under the illumination of 1550 nm infrared light. All of the results demonstrate that the as-prepared Sn-catalyzed GaSb NWs are promising for application in next-generation electronics and optoelectronics.
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Affiliation(s)
- Jiamin Sun
- School of Microelectronics , Shandong University , Jinan 250100 , P. R. China
- Shenzhen Research Institute of Shandong University , Shenzhen 518057 , P. R. China
| | - Meng Peng
- State Key Laboratory of Infrared Physics , Shanghai Institute of Technical Physics, Chinese Academy of Sciences , Shanghai 200083 , P. R. China
- Wuhan National Laboratory for Optoelectronics , Huazhong University of Science and Technology , Wuhan 430074 , China
| | - Yushuang Zhang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, College of Materials Science and Engineering , Hunan University , Changsha 410082 , P. R. China
| | - Lei Zhang
- SEU-FEI Nano-Pico Center, Key Lab of MEMS of Ministry of Education, Collaborative Innovation Center for Micro/Nano Fabrication, Device and System , Southeast University , Nanjing 210096 , P. R. China
| | - Rui Peng
- School of Physics , Shandong University , Jinan 250100 , P. R. China
| | - Chengcheng Miao
- School of Microelectronics , Shandong University , Jinan 250100 , P. R. China
| | - Dong Liu
- School of Microelectronics , Shandong University , Jinan 250100 , P. R. China
| | - Mingming Han
- School of Microelectronics , Shandong University , Jinan 250100 , P. R. China
- Shenzhen Research Institute of Shandong University , Shenzhen 518057 , P. R. China
| | - Runfa Feng
- School of Physics , Shandong University , Jinan 250100 , P. R. China
| | - Yandong Ma
- School of Physics , Shandong University , Jinan 250100 , P. R. China
| | - Ying Dai
- School of Physics , Shandong University , Jinan 250100 , P. R. China
| | - Longbing He
- SEU-FEI Nano-Pico Center, Key Lab of MEMS of Ministry of Education, Collaborative Innovation Center for Micro/Nano Fabrication, Device and System , Southeast University , Nanjing 210096 , P. R. China
| | - Chongxin Shan
- Henan Key Laboratory of Diamond Optoelectronic Materials and Devices, School of Physics and Engineering , Zhengzhou University , Zhengzhou 450001 , China
| | - Anlian Pan
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, College of Materials Science and Engineering , Hunan University , Changsha 410082 , P. R. China
| | - Weida Hu
- State Key Laboratory of Infrared Physics , Shanghai Institute of Technical Physics, Chinese Academy of Sciences , Shanghai 200083 , P. R. China
| | - Zai-Xing Yang
- School of Microelectronics , Shandong University , Jinan 250100 , P. R. China
- Shenzhen Research Institute of Shandong University , Shenzhen 518057 , P. R. China
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