1
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Sun W, Liu Z, Xu Z, Zhang Y. Unravelling the interplay of local structure and valence transitions in Ce-doped CaYAlO 4 luminescent materials. LUMINESCENCE 2024; 39:e4591. [PMID: 37675627 DOI: 10.1002/bio.4591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 08/28/2023] [Accepted: 09/03/2023] [Indexed: 09/08/2023]
Abstract
Cerium has been widely used as a dopant in luminescent materials due to its unique electronic configurations. It is generally anticipated that the luminescence properties of rare-earth-doped materials are closely related to the local environment of activators, especially for Ce3+ . In addition, it is convenient to modulate its emission wavelength by adjusting the composition and structure. In this study, we systematically analyzed the microstructure of the Ce-doped CaYAlO4 system at atomic resolution. The quantitive results indicated that the structure distortion greatly influenced the valence state of the Ce dopant, which is critical to its luminescence efficiency. In addition, valence variations also exist from surface to inner structure due to the big distortion area around the surface. Our results unravel the interplay of local structure and valence transitions in Ce-doped aluminate phosphors, which has the potential to be applied in other luminescent materials.
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Affiliation(s)
- Wenhao Sun
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, China
| | - Zihui Liu
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, China
| | - Zhipeng Xu
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, China
| | - Yang Zhang
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, China
- Center of Advanced Analysis & Gene Sequencing, Zhengzhou University, Zhengzhou, China
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2
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Li D, Chen Q, Chun J, Fichthorn K, De Yoreo J, Zheng H. Nanoparticle Assembly and Oriented Attachment: Correlating Controlling Factors to the Resulting Structures. Chem Rev 2023; 123:3127-3159. [PMID: 36802554 DOI: 10.1021/acs.chemrev.2c00700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Nanoparticle assembly and attachment are common pathways of crystal growth by which particles organize into larger scale materials with hierarchical structure and long-range order. In particular, oriented attachment (OA), which is a special type of particle assembly, has attracted great attention in recent years because of the wide range of material structures that result from this process, such as one-dimensional (1D) nanowires, two-dimensional (2D) sheets, three-dimensional (3D) branched structures, twinned crystals, defects, etc. Utilizing in situ transmission electron microscopy techniques, researchers observed orientation-specific forces that act over short distances (∼1 nm) from the particle surfaces and drive the OA process. Integrating recently developed 3D fast force mapping via atomic force microscopy with theories and simulations, researchers have resolved the near-surface solution structure, the molecular details of charge states at particle/fluid interfaces, inhomogeneity of surface charges, and dielectric/magnetic properties of particles that influence short- and long-range forces, such as electrostatic, van der Waals, hydration, and dipole-dipole forces. In this review, we discuss the fundamental principles for understanding particle assembly and attachment processes, and the controlling factors and resulting structures. We review recent progress in the field via examples of both experiments and modeling, and discuss current developments and the future outlook.
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Affiliation(s)
- Dongsheng Li
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Qian Chen
- Department of Materials Science and Engineering, University of Illinois, Urbana, Illinois 61801, United States
| | - Jaehun Chun
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
- Levich Institute and Department of Chemical Engineering, CUNY City College of New York; New York, New York 10031, United States
| | - Kristen Fichthorn
- Department of Chemical Engineering, The Pennsylvania State University; University Park, Pennsylvania 16802, United States
| | - James De Yoreo
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
- Department of Materials Science and Engineering, University of Washington, Seattle Washington 98195, United States
| | - Haimei Zheng
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley California 94720, United States
- Department of Materials Science and Engineering, University of California, Berkeley, California 94720, United States
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3
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Zhang Y, Yang X, Zhao SN, Zhai Y, Pang X, Lin J. Recent Developments of Microscopic Study for Lanthanide and Manganese Doped Luminescent Materials. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2205014. [PMID: 36310419 DOI: 10.1002/smll.202205014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 09/28/2022] [Indexed: 06/16/2023]
Abstract
Luminescent materials are indispensable for applications in lighting, displays and photovoltaics, which can transfer, absorb, store and utilize light energy. Their performance is closely related with their size and morphologies, exact atomic arrangement, and local configuration about photofunctional centers. Advanced electron microscopy-based techniques have enabled the possibility to study nanostructures with atomic resolution. Especially, with the advanced micro-electro-mechanical systems, it is able to characterize the luminescent materials at the atomic scale under various environments, providing a deep understanding of the luminescent mechanism. Accordingly, this review summarizes the recent achievements of microscopic study to directly image the microstructure and local environment of activators in lanthanide and manganese (Ln/Mn2+ )-doped luminescent materials, including: 1) bulk materials, the typical systems are nitride/oxynitride phosphors; and 2) nanomaterials, such as nanocrystals (hexagonal-phase NaLnF4 and perovskite) and 2D nanosheets (Ca2 Ta3 O10 and MoS2 ). Finally, the challenges and limitations are highlighted, and some possible solutions to facilitate the developments of advanced luminescent materials are provided.
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Affiliation(s)
- Yang Zhang
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Xuewei Yang
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Shu-Na Zhao
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Yalong Zhai
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Xinchang Pang
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Jun Lin
- State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China
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4
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Polivtseva S, Kois J, Kruzhilina T, Kaupmees R, Klopov M, Molaiyan P, van Gog H, van Huis MA, Volobujeva O. Solution-Mediated Inversion of SnSe to Sb 2Se 3 Thin-Films. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:2898. [PMID: 36079936 PMCID: PMC9458253 DOI: 10.3390/nano12172898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Revised: 08/18/2022] [Accepted: 08/19/2022] [Indexed: 06/15/2023]
Abstract
New facile and controllable approaches to fabricating metal chalcogenide thin films with adjustable properties can significantly expand the scope of these materials in numerous optoelectronic and photovoltaic devices. Most traditional and especially wet-chemical synthetic pathways suffer from a sluggish ability to regulate the composition and have difficulty achieving the high-quality structural properties of the sought-after metal chalcogenides, especially at large 2D length scales. In this effort, and for the first time, we illustrated the fast and complete inversion of continuous SnSe thin-films to Sb2Se3 using a scalable top-down ion-exchange approach. Processing in dense solution systems yielded the formation of Sb2Se3 films with favorable structural characteristics, while oxide phases, which are typically present in most Sb2Se3 films regardless of the synthetic protocols used, were eliminated. Density functional theory (DFT) calculations performed on intermediate phases show strong relaxations of the atomic lattice due to the presence of substitutional and vacancy defects, which likely enhances the mobility of cationic species during cation exchange. Our concept can be applied to customize the properties of other metal chalcogenides or manufacture layered structures.
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Affiliation(s)
- Svetlana Polivtseva
- Department of Materials and Environmental Technology, School of Engineering, TalTech, Ehitajate tee 5, 19086 Tallinn, Estonia
| | - Julia Kois
- Auramet Solutions OÜ, Kalliomäentie 1B, 02920 Espoo, Finland
| | - Tatiana Kruzhilina
- Department of Materials and Environmental Technology, School of Engineering, TalTech, Ehitajate tee 5, 19086 Tallinn, Estonia
| | - Reelika Kaupmees
- Department of Materials and Environmental Technology, School of Engineering, TalTech, Ehitajate tee 5, 19086 Tallinn, Estonia
| | - Mihhail Klopov
- Department of Cybernetics, School of Science, TalTech, Ehitajate tee 5, 19086 Tallinn, Estonia
| | - Palanivel Molaiyan
- Research Unit of Sustainable Chemistry, Faculty of Technology, University of Oulu, Pentti Kaiteran katu 1, 90014 Oulu, Finland
| | - Heleen van Gog
- Nanostructured Materials and Interfaces, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Marijn A. van Huis
- Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | - Olga Volobujeva
- Department of Materials and Environmental Technology, School of Engineering, TalTech, Ehitajate tee 5, 19086 Tallinn, Estonia
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5
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Salzmann B, Wit JD, Li C, Arenas-Esteban D, Bals S, Meijerink A, Vanmaekelbergh D. Two-Dimensional CdSe-PbSe Heterostructures and PbSe Nanoplatelets: Formation, Atomic Structure, and Optical Properties. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2022; 126:1513-1522. [PMID: 35116087 PMCID: PMC8802322 DOI: 10.1021/acs.jpcc.1c09412] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/30/2021] [Indexed: 06/12/2023]
Abstract
Cation exchange enables the preparation of nanocrystals (NCs), which are not reachable by direct synthesis methods. In this work, we applied Pb2+-for-Cd2+ cation exchange on CdSe nanoplatelets (NPLs) to prepare two-dimensional CdSe-PbSe heterostructures and PbSe NPLs. Lowering the reaction temperature slowed down the rate of cation exchange, making it possible to characterize the intermediary NCs ex situ with atomically resolved high-angle annular dark-field scanning transmission electron microscopy and optical spectroscopy. We observe that the Pb2+-for-Cd2+ cation exchange starts from the vertices of the NPLs and grows into the zinc blende CdSe (zb-CdSe) lattice as a rock salt PbSe phase (rs-PbSe), while the anion (selenium) sublattice is being preserved. In agreement with previous works on CdTe-PbTe films, the interfaces between zb-CdSe and rs-PbSe consist of shared {001} and {011} planes. The final PbSe NPLs are highly crystalline and contain protrusions at the edges, which are slightly rotated, indicating an atomic reconfiguration of material. The growth of PbSe domains into CdSe NPLs could also be monitored by the emission peak shift as a function of the exchange time. Temperature-dependent emission measurements confirm a size-dependent change of the band gap energy with temperature and reveal a strong influence of the anisotropic shape. Time-resolved photoluminescence measurements between 4 and 30 K show a dark-bright exciton-state splitting different from PbSe QDs with three-dimensional quantum confinement.
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Affiliation(s)
- Bastiaan
B.V. Salzmann
- Condensed
Matter & Interfaces, Debye Institute for Nanomaterials Science, Utrecht University, 3508TA Utrecht, The Netherlands
| | - Jur de Wit
- Condensed
Matter & Interfaces, Debye Institute for Nanomaterials Science, Utrecht University, 3508TA Utrecht, The Netherlands
| | - Chen Li
- EMAT
and Nanolab Centre of Excellence, Antwerp
University, 2020 Antwerp, Belgium
| | | | - Sara Bals
- EMAT
and Nanolab Centre of Excellence, Antwerp
University, 2020 Antwerp, Belgium
| | - Andries Meijerink
- Condensed
Matter & Interfaces, Debye Institute for Nanomaterials Science, Utrecht University, 3508TA Utrecht, The Netherlands
| | - Daniel Vanmaekelbergh
- Condensed
Matter & Interfaces, Debye Institute for Nanomaterials Science, Utrecht University, 3508TA Utrecht, The Netherlands
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6
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Galle T, Spittel D, Weiß N, Shamraienko V, Decker H, Georgi M, Hübner R, Metzkow N, Steinbach C, Schwarz D, Lesnyak V, Eychmüller A. Simultaneous Ligand and Cation Exchange of Colloidal CdSe Nanoplatelets toward PbSe Nanoplatelets for Application in Photodetectors. J Phys Chem Lett 2021; 12:5214-5220. [PMID: 34043348 DOI: 10.1021/acs.jpclett.1c01362] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Cation exchange emerged as a versatile tool to obtain a variety of nanocrystals not yet available via a direct synthesis. Reduced reaction times and moderate temperatures make the method compatible with anisotropic nanoplatelets (NPLs). However, the subtle thermodynamic and kinetic factors governing the exchange require careful control over the reaction parameters to prevent unwanted restructuring. Here, we capitalize on the research success of CdSe NPLs by transforming them into PbSe NPLs suitable for optoelectronic applications. In a two-phase mixture of hexane/N-methylformamide, the oleate-capped CdSe NPLs simultaneously undergo a ligand exchange to NH4I and a cation exchange reaction to PbSe. Their morphology and crystal structure are well-preserved as evidenced by electron microscopy and powder X-ray diffraction. We demonstrate the successful ligand exchange and associated electronic coupling of individual NPLs by fabricating a simple photodetector via spray-coating on a commercial substrate. Its optoelectronic characterization reveals a fast light response at low operational voltages.
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Affiliation(s)
- Tom Galle
- Physical Chemistry, TU Dresden, Zellescher Weg 19, 01069 Dresden, Germany
| | - Daniel Spittel
- Physical Chemistry, TU Dresden, Zellescher Weg 19, 01069 Dresden, Germany
| | - Nelli Weiß
- Physical Chemistry, TU Dresden, Zellescher Weg 19, 01069 Dresden, Germany
| | | | - Helena Decker
- Physical Chemistry, TU Dresden, Zellescher Weg 19, 01069 Dresden, Germany
| | - Maximilian Georgi
- Physical Chemistry, TU Dresden, Zellescher Weg 19, 01069 Dresden, Germany
| | - René Hübner
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstr. 400, 01328 Dresden, Germany
| | - Nadia Metzkow
- Physical Chemistry, TU Dresden, Zellescher Weg 19, 01069 Dresden, Germany
| | - Christine Steinbach
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany
| | - Dana Schwarz
- Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany
| | - Vladimir Lesnyak
- Physical Chemistry, TU Dresden, Zellescher Weg 19, 01069 Dresden, Germany
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7
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Unique Cation Exchange in Nanocrystal Matrix via Surface Vacancy Engineering Overcoming Chemical Kinetic Energy Barriers. Chem 2020. [DOI: 10.1016/j.chempr.2020.08.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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8
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Cheng F, Lian L, Li L, Rao J, Li C, Qi T, Zhang Z, Zhang J, Gao Y. Hybrid Growth Modes of PbSe Nanocrystals with Oriented Attachment and Grain Boundary Migration. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2019; 6:1802202. [PMID: 31065525 PMCID: PMC6498134 DOI: 10.1002/advs.201802202] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 01/18/2019] [Indexed: 05/31/2023]
Abstract
The growth of nanocrystals has widely been researched recently through an in situ high-resolution transmission electron microscopy technique, which reveals the process of morphological and structural evolutions. For nanocrystals, the underlying growth modes are mostly determined by growth environment and crystal morphology. Here, the direct growth process of the PbSe nanocrystals via controlling the temperature is clearly observed. The results show that the PbSe nanocrystals start growth following oriented attachment growth mode, and then change to growth with grain boundary migration at moderate temperature as the heat activated nanocrystals gather together with decreased degree of freedom for crystal rotation. During the grain boundary migration, the smaller nanocrystals are inclined to be assimilated by larger ones through interfacial atom reconfigurations, which are observed to take place through strain mediated atom migration. The growth mode changes in different growth states with a hybrid growth mode of oriented attachment and grain boundary migration during the whole growth process.
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Affiliation(s)
- Feng Cheng
- Center for Nanoscale Characterization & DevicesWuhan National Laboratory for OptoelectronicsHuazhong University of Science and Technology1037 Luoyu RoadWuhanHubei430074China
| | - Linyuan Lian
- Engineering Research Center for Functional CeramicsMinistry of Education, School of Optical and Electronic InformationHuazhong University of Science and Technology1037 Luoyu RoadWuhanHubei430074China
| | - Luying Li
- Center for Nanoscale Characterization & DevicesWuhan National Laboratory for OptoelectronicsHuazhong University of Science and Technology1037 Luoyu RoadWuhanHubei430074China
| | - Jiangyu Rao
- Center for Nanoscale Characterization & DevicesWuhan National Laboratory for OptoelectronicsHuazhong University of Science and Technology1037 Luoyu RoadWuhanHubei430074China
| | - Chen Li
- Center for Nanoscale Characterization & DevicesWuhan National Laboratory for OptoelectronicsHuazhong University of Science and Technology1037 Luoyu RoadWuhanHubei430074China
| | - Tianyu Qi
- Center for Nanoscale Characterization & DevicesWuhan National Laboratory for OptoelectronicsHuazhong University of Science and Technology1037 Luoyu RoadWuhanHubei430074China
| | - Zhi Zhang
- School of PhysicsHuazhong University of Science and Technology1037 Luoyu RoadWuhanHubei430074China
| | - Jianbing Zhang
- Engineering Research Center for Functional CeramicsMinistry of Education, School of Optical and Electronic InformationHuazhong University of Science and Technology1037 Luoyu RoadWuhanHubei430074China
| | - Yihua Gao
- School of PhysicsHuazhong University of Science and Technology1037 Luoyu RoadWuhanHubei430074China
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9
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Casu A, Falqui A. Developments of cation-exchange by in situ electron microscopy. ADVANCES IN PHYSICS: X 2019. [DOI: 10.1080/23746149.2019.1633957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Affiliation(s)
- Alberto Casu
- Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Andrea Falqui
- Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
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10
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Huang X, Liu Z, Millet MM, Dong J, Plodine M, Ding F, Schlögl R, Willinger MG. In Situ Atomic-Scale Observation of Surface-Tension-Induced Structural Transformation of Ag-NiP x Core-Shell Nanocrystals. ACS NANO 2018; 12:7197-7205. [PMID: 29924929 DOI: 10.1021/acsnano.8b03106] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The properties of nanocrystals are highly dependent on their morphology, composition, and structure. Tailored synthesis over these parameters is successfully applied for the production of nanocrystals with desired properties for specific applications. However, in order to obtain full control over the properties, the behavior of nanocrystals under external stimuli and application conditions needs to be understood. Herein, using Ag-NiP x nanocrystals as a model system, we investigate the structural evolution upon thermal treatment by in situ aberration-corrected scanning transmission electron microscopy. A combination of real-time imaging with elemental analysis enables the observation of the transformation from a Ag-NiP x core-shell configuration to a Janus structure at the atomic scale. The transformation occurs through dewetting and crystallization of the NiP x shell and is accompanied by surface segregation of Ag. Further temperature increase leads to a complete sublimation of Ag and formation of individual Ni12P5 nanocrystals. The transformation is rationalized by theoretical modeling based on density functional theory calculations. Our model suggests that the transformation is driven by changes of the surface energy of NiP x and the interfacial energy between NiP x and Ag. The direct observation of atomistic dynamics during thermal-treatment-induced structural modification will help to understand more complex transformations that are induced by aging over time or the interaction with a reactive gas phase in applications such as catalysis.
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Affiliation(s)
- Xing Huang
- Department of Heterogeneous Reactions , Max Planck Institute for Chemical Energy Conversion , 45470 Mülheim an der Ruhr , Germany
- Department of Inorganic Chemistry , Fritz Haber Institute of Max Planck Society , Faradayweg 4-6 , 14195 Berlin , Germany
| | - Zhongqiang Liu
- Department of Physics , Qufu Normal University , Qufu 273165 , P.R. China
- Center for Multidimensional Carbon Materials , Institute for Basic Science (IBS) , Ulsan 44919 , Republic of Korea
| | - Marie-Mathilde Millet
- Department of Inorganic Chemistry , Fritz Haber Institute of Max Planck Society , Faradayweg 4-6 , 14195 Berlin , Germany
| | - Jichen Dong
- Center for Multidimensional Carbon Materials , Institute for Basic Science (IBS) , Ulsan 44919 , Republic of Korea
| | - Milivoj Plodine
- Department of Inorganic Chemistry , Fritz Haber Institute of Max Planck Society , Faradayweg 4-6 , 14195 Berlin , Germany
- Division of Material Physics , Rudjer Boskovic Institute , Bijenicka 54 , 10000 Zagreb , Croatia
| | - Feng Ding
- Center for Multidimensional Carbon Materials , Institute for Basic Science (IBS) , Ulsan 44919 , Republic of Korea
- Department of Materials Science and Engineering , Ulsan National Institute of Science and Technology (UNIST) , Ulsan 44919 , Republic of Korea
| | - Robert Schlögl
- Department of Heterogeneous Reactions , Max Planck Institute for Chemical Energy Conversion , 45470 Mülheim an der Ruhr , Germany
- Department of Inorganic Chemistry , Fritz Haber Institute of Max Planck Society , Faradayweg 4-6 , 14195 Berlin , Germany
| | - Marc-Georg Willinger
- Department of Inorganic Chemistry , Fritz Haber Institute of Max Planck Society , Faradayweg 4-6 , 14195 Berlin , Germany
- Scientific Center for Optical and Electron Microscopy , ETH Zürich , Auguste-Piccard-Hof 1 , 8093 Zürich , Switzerland
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11
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van Overbeek C, Peters JL, van Rossum SAP, Smits M, van Huis MA, Vanmaekelbergh D. Interfacial Self-Assembly and Oriented Attachment in the Family of PbX (X = S, Se, Te) Nanocrystals. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2018; 122:12464-12473. [PMID: 29930743 PMCID: PMC6004561 DOI: 10.1021/acs.jpcc.8b01876] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 05/11/2018] [Indexed: 05/26/2023]
Abstract
The realization of materials with new optoelectronic properties draws much scientific attention toward the field of nanocrystal superstructures. Low-dimensional superstructures created by interfacial assembly and oriented attachment of PbSe nanocrystals are a striking example because theory showed that PbSe sheets with a honeycomb geometry possess non-trivial flat bands and Dirac cones in the valence and conduction bands. Here, we report on the formation of one-dimensional linear and zigzag structures and two-dimensional (2D) square and honeycomb structures for the entire lead chalcogenide family: PbX (X = S, Se, Te). We observe that PbTe, with a lower bulk melting temperature and enthalpy of formation than those of PbSe, shows a higher nanocrystal surface reactivity, such that the surface must be passivated and the reaction conditions moderated to obtain reasonably ordered superstructures. The present findings constitute a step forward in the realization of a larger family of atomically coherent 2D superstructures with variable IV-VI and II-VI compositions and with electronic properties dictated by the nanogeometry.
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12
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Paul S, Ghosh S, De SK. Efficient Charge Separation in Plasmonic ZnS@Sn:ZnO Nanoheterostructure: Nanoscale Kirkendall Effect and Enhanced Photophysical Properties. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:4324-4339. [PMID: 29571262 DOI: 10.1021/acs.langmuir.8b00442] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Tetravalent Sn doped ZnO nanocrystals show excellent plasmonic absorbance in the visible region. Plasmonic ZnS@Sn:ZnO core-shell heterostructures have been synthesized by the anion exchange process where the O2- is exchanged by S2- anion. An increase of sulfur concentration induces interior hollow structures arising from the different diffusion rates of O2- and S2- ions. Gradual transformation of wurtztie ZnO nanocrystals in the anion exchange process stabilizes the wurtzite crystalline phase of ZnS. Carrier concentration and various types of intrinsic defect states in both ZnO and ZnS result in ultraviolet, blue, and green emissions. The coexistence of exciton-plasmon coupling in the same nanoparticle and efficient electron-hole separation in type II heterostructure increases the photocatalytic activity and photo current gain.
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Affiliation(s)
- Sumana Paul
- Department of Materials Science , Indian Association for the Cultivation of Science , Kolkata 700032 , India
| | - Sirshendu Ghosh
- Department of Materials Science , Indian Association for the Cultivation of Science , Kolkata 700032 , India
| | - Subodh Kumar De
- Department of Materials Science , Indian Association for the Cultivation of Science , Kolkata 700032 , India
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13
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Lee S, Wang Y, Liu Y, Lee D, Lee K, Lee DC, Lian T. Exciton dynamics in cation-exchanged CdSe/PbSe nanorods: The role of defects. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.04.047] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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14
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Huang X, Jones T, Fan H, Willinger MG. Real-time atomic scale observation of void formation and anisotropic growth in II-VI semiconducting ribbons. NANOSCALE 2017; 9:12479-12485. [PMID: 28816305 DOI: 10.1039/c7nr02231j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Void formation in semiconductors is generally considered to be deteriorating. However, for some systems, void formation and evolution are beneficial and can be used for the fabrication of novel nanostructures. In either scenario, the understanding of void formation and evolution is of both scientific and technical high importance. Herein, using ZnS ribbons as an example, we report real-time observations of void formation and the kinetics of growth at the nano- and atomic scales upon heating. Direct imaging reveals that voids, created by a focused electron beam in wurtzite (WZ) ribbons, have a rectangular shape elongated along the <0001> direction. The voids are enclosed by low-surface-energy planes including {01-10} and {2-1-10}, with minor contribution from the higher-energy {0001} planes. Driven by thermodynamics to minimize surface energy, the voids grow straight along the [000±1] directions, exhibiting a strong anisotropy. Occasionally, we observe oscillatory kinetics involving periodic void growth and shrinkage, likely due to the fluctuation of the local chemical potential leading to a transitional kinetic state. We also reveal that the morphology and growth kinetics of voids are highly structure-dependent. Real-time observation during void growth through the complex WZ-zinc blende (ZB)-WZ structure shows that the void, with an initial elongated rectangular morphology in the WZ domain, transforms into a different shape, dominated by the {110} surfaces, after migrating to a domain of the ZB structure. However, when the void moves from the ZB to the WZ domain, it transforms back into a rectangular shape followed by fast growth along the [0001] direction. Our experimental results, together with density functional theory (DFT) calculations, provide valuable insights into the mechanistic understanding of void formation and evolution in semiconductors. More importantly, our study may shed light on new pathways for the morphological modulation of nanostructures by utilizing the intrinsic anisotropy of void evolution in WZ semiconductors.
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Affiliation(s)
- Xing Huang
- Department of Inorganic Chemistry, Fritz-Haber Institute of Max-Planck Society, Faradayweg 4-6, 14195, Berlin, Germany.
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15
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Chalasani R, Pekin A, Rabkin A, Abutbul RE, Diéguez O, Kauffmann Y, Golan Y, Kohn A. Mapping Charge Distribution in Single PbS Core - CdS Arm Nano-Multipod Heterostructures by Off-Axis Electron Holography. NANO LETTERS 2017; 17:2778-2787. [PMID: 28388052 DOI: 10.1021/acs.nanolett.6b04957] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We synthesized PbS core-CdS arm nanomultipod heterostructures (NMHs) that exhibit PbS{111}/CdS{0002} epitaxial relations. The PbS-CdS interface is chemically sharp as determined by aberration corrected transmission electron microscopy (TEM) and compared to density functional theory (DFT) calculations. Ensemble fluorescence measurements show quenching of the optical signal from the CdS arms indicating charge separation due to the heterojunction with PbS. A finite-element three-dimensional (3D) calculation of the Poisson equation shows a type-I heterojunction, which would prevent recombination in the CdS arm after optical excitation. To examine charge redistribution, we used off-axis electron holography (OAEH) in the TEM to map the electrostatic potential across an individual heterojunction. Indeed, a built-in potential of 500 mV is estimated across the junction, though as opposed to the thermal equilibrium calculations significant accumulation of positive charge at the CdS side of the interface is detected. We conclude that the NMH multipod geometry prevents efficient removal of generated charge carriers by the high energy electrons of the TEM. Simulations of generated electron-hole pairs in the insulated CdS arm of the NMH indeed show charge accumulation in agreement with the experimental measurements. Thus, we show that OAEH can be used as a complementary methodology to ensemble measurements by mapping the charge distribution in single NMHs with complex geometries.
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Affiliation(s)
| | | | | | | | | | - Yaron Kauffmann
- Department of Materials Science and Engineering, Technion - Israel Institute of Technology , Haifa 32000, Israel
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16
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Zhang Q, Yin K, Dong H, Zhou Y, Tan X, Yu K, Hu X, Xu T, Zhu C, Xia W, Xu F, Zheng H, Sun L. Electrically driven cation exchange for in situ fabrication of individual nanostructures. Nat Commun 2017; 8:14889. [PMID: 28401911 PMCID: PMC5394283 DOI: 10.1038/ncomms14889] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 02/09/2017] [Indexed: 11/09/2022] Open
Abstract
Cation exchange (CE) has been recognized as a particularly powerful tool for the synthesis of heterogeneous nanocrystals. At present, CE can be divided into two categories, namely ion solvation-driven CE reaction and thermally activated CE reaction. Here we report an electrically driven CE reaction to prepare individual nanostructures inside a transmission electron microscope. During the process, Cd is eliminated due to Ohmic heating, whereas Cu+ migrates into the crystal driven by the electrical field force. Contrast experiments reveal that the feasibility of electrically driven CE is determined by the structural similarity of the sulfur sublattices between the initial and final phases, and the standard electrode potentials of the active electrodes. Our experimental results demonstrate a strategy for the selective growth of individual nanocrystals and provide crucial insights into understanding of the microscopic pathways leading to the formation of heterogeneous structures. Cation exchange, traditionally driven by ion solvation or thermal activation, is a robust approach for preparing heterogeneous nanostructures but lacks selectivity for preparation of individual nanocrystals. Here, the authors report an electrically driven cation exchange reaction that enables them to fabricate individual nanocrystals with high selectivity.
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Affiliation(s)
- Qiubo Zhang
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronic Science and Engineering, Southeast University, Nanjing 210018, China
| | - Kuibo Yin
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronic Science and Engineering, Southeast University, Nanjing 210018, China
| | - Hui Dong
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronic Science and Engineering, Southeast University, Nanjing 210018, China
| | - Yilong Zhou
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronic Science and Engineering, Southeast University, Nanjing 210018, China
| | - Xiaodong Tan
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronic Science and Engineering, Southeast University, Nanjing 210018, China
| | - Kaihao Yu
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronic Science and Engineering, Southeast University, Nanjing 210018, China
| | - Xiaohui Hu
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronic Science and Engineering, Southeast University, Nanjing 210018, China.,College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, China
| | - Tao Xu
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronic Science and Engineering, Southeast University, Nanjing 210018, China
| | - Chao Zhu
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronic Science and Engineering, Southeast University, Nanjing 210018, China
| | - Weiwei Xia
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronic Science and Engineering, Southeast University, Nanjing 210018, China
| | - Feng Xu
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronic Science and Engineering, Southeast University, Nanjing 210018, China
| | - Haimei Zheng
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.,Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA
| | - Litao Sun
- SEU-FEI Nano-Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronic Science and Engineering, Southeast University, Nanjing 210018, China.,Center for Advanced Materials and Manufacture, Joint Research Institute of Southeast University and Monash University, Suzhou 215123, China
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17
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Cosseddu S, Infante I. Force Field Parametrization of Colloidal CdSe Nanocrystals Using an Adaptive Rate Monte Carlo Optimization Algorithm. J Chem Theory Comput 2016; 13:297-308. [PMID: 28068776 DOI: 10.1021/acs.jctc.6b01089] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
In a typical colloidal CdSe nanocrystal more than 50% of the atoms are located at the surface. These atoms can give rise to electronic traps that can deteriorate the performance of optoelectronic devices made of these nanomaterials. A key challenge in this field is thus to understand with atomistic detail the chemical processes occurring at the nanocrystal surface. Molecular dynamics simulations represent an important tool to unveil these processes, but its implementation is strongly limited by the difficulties of finely tuning classical force fields parameters, primarily caused by the unavailability of experimental data of these materials that are suitable in the parametrization procedures. In this work, we present a general scheme to produce force field parameters from first-principles calculations. This approach is based on a newly developed stochastic optimization algorithm called Adaptive Rate Monte Carlo, which is designed to be robust, accurate, easy-to-use, and flexible enough to be straightforwardly extended to other nanomaterials. We demonstrate that our algorithm provides a set of parameters capable of satisfactorily describing nonstoichiometric CdSe nanocrystals passivated with oleate ligands akin to experimental conditions. We also demonstrate that our new parameters are robust enough to be transferable among crystal structures and nanocrystals of increasing sizes up to the bulk.
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Affiliation(s)
- Salvatore Cosseddu
- Department of Theoretical Chemistry and Amsterdam Center for Multiscale Modeling (ACMM), VU University Amsterdam , De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| | - Ivan Infante
- Department of Theoretical Chemistry and Amsterdam Center for Multiscale Modeling (ACMM), VU University Amsterdam , De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
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18
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Kriegner D, Sytnyk M, Groiss H, Yarema M, Grafeneder W, Walter P, Dippel AC, Meffert M, Gerthsen D, Stangl J, Heiss W. Galvanic Exchange in Colloidal Metal/Metal-Oxide Core/Shell Nanocrystals. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2016; 120:19848-19855. [PMID: 27635186 PMCID: PMC5018861 DOI: 10.1021/acs.jpcc.6b06405] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 08/15/2016] [Indexed: 05/29/2023]
Abstract
While galvanic exchange is commonly applied to metallic nanoparticles, recently its applicability was expanded to metal-oxides. Here the galvanic exchange is studied in metal/metal-oxide core/shell nanocrystals. In particular Sn/SnO2 is treated by Ag+, Pt2+, Pt4+, and Pd2+. The conversion dynamics is monitored by in situ synchrotron X-ray diffraction. The Ag+ treatment converts the Sn cores to the intermetallic Ag x Sn (x ∼ 4) phase, by changing the core's crystal structure. For the analogous treatment by Pt2+, Pt4+, and Pd2+, such a galvanic exchange is not observed. This different behavior is caused by the semipermeability of the naturally formed SnO2 shell, which allows diffusion of Ag+ but protects the nanocrystal cores from oxidation by Pt and Pd ions.
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Affiliation(s)
- Dominik Kriegner
- Institute
of Semiconductor and Solid State Physics, Johannes Kepler University, Altenberger Straße 69, A-4040 Linz, Austria
- Department
of Condensed Matter Physics, Charles University
Prague, Ke Karlovu 5, 121 16 Praha 2, Czech Republic
| | - Mykhailo Sytnyk
- Institute
of Semiconductor and Solid State Physics, Johannes Kepler University, Altenberger Straße 69, A-4040 Linz, Austria
- Materials
Science Department (Materials for Electronics and Energy Technology), Friedrich-Alexander Universität, Fürtherstrasse 250, D-90429 Nürnberg, Germany
| | - Heiko Groiss
- Christian
Doppler Laboratory for Microscopic and Spectroscopic Material Characterization,
Center for Surface and Nanoanalytics (ZONA), Johannes Kepler University, Altenberger Straße 69, A-4040 Linz, Austria
- Laboratory
for Electron Microscopy, Karlsruhe Institute
of Technology, D-76131 Karlsruhe, Germany
| | - Maksym Yarema
- Institute
of Semiconductor and Solid State Physics, Johannes Kepler University, Altenberger Straße 69, A-4040 Linz, Austria
| | - Wolfgang Grafeneder
- Institute
of Semiconductor and Solid State Physics, Johannes Kepler University, Altenberger Straße 69, A-4040 Linz, Austria
| | - Peter Walter
- Deutsches
Elektronen-Synchrotron DESY, Notkestraße 85, D-22607 Hamburg, Germany
| | - Ann-Christin Dippel
- Deutsches
Elektronen-Synchrotron DESY, Notkestraße 85, D-22607 Hamburg, Germany
| | - Matthias Meffert
- Laboratory
for Electron Microscopy, Karlsruhe Institute
of Technology, D-76131 Karlsruhe, Germany
| | - Dagmar Gerthsen
- Laboratory
for Electron Microscopy, Karlsruhe Institute
of Technology, D-76131 Karlsruhe, Germany
| | - Julian Stangl
- Institute
of Semiconductor and Solid State Physics, Johannes Kepler University, Altenberger Straße 69, A-4040 Linz, Austria
| | - Wolfgang Heiss
- Institute
of Semiconductor and Solid State Physics, Johannes Kepler University, Altenberger Straße 69, A-4040 Linz, Austria
- Materials
Science Department (Materials for Electronics and Energy Technology), Friedrich-Alexander Universität, Fürtherstrasse 250, D-90429 Nürnberg, Germany
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19
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Tu R, Xie Y, Bertoni G, Lak A, Gaspari R, Rapallo A, Cavalli A, Trizio LD, Manna L. Influence of the Ion Coordination Number on Cation Exchange Reactions with Copper Telluride Nanocrystals. J Am Chem Soc 2016; 138:7082-90. [PMID: 27177274 PMCID: PMC5736242 DOI: 10.1021/jacs.6b02830] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Cu2–xTe nanocubes were used
as starting seeds to access metal telluride nanocrystals by cation
exchanges at room temperature. The coordination number of the entering
cations was found to play an important role in dictating the reaction
pathways. The exchanges with tetrahedrally coordinated cations (i.e.,
with coordination number 4), such as Cd2+ or Hg2+, yielded monocrystalline CdTe or HgTe nanocrystals with Cu2–xTe/CdTe or Cu2–xTe/HgTe Janus-like heterostructures as intermediates. The formation
of Janus-like architectures was attributed to the high diffusion rate
of the relatively small tetrahedrally coordinated cations, which could
rapidly diffuse in the Cu2–xTe
NCs and nucleate the CdTe (or HgTe) phase in a preferred region of
the host structure. Also, with both Cd2+ and Hg2+ ions the exchange led to wurtzite CdTe and HgTe phases rather than
the more stable zinc-blende ones, indicating that the anion framework
of the starting Cu2–xTe particles
could be more easily deformed to match the anion framework of the
metastable wurtzite structures. As hexagonal HgTe had never been reported
to date, this represents another case of metastable new phases that
can only be accessed by cation exchange. On the other hand, the exchanges
involving octahedrally coordinated ions (i.e., with coordination number
6), such as Pb2+ or Sn2+, yielded rock-salt
polycrystalline PbTe or SnTe nanocrystals with Cu2–xTe@PbTe or Cu2–xTe@SnTe core@shell architectures at the early stages of the exchange
process. In this case, the octahedrally coordinated ions are probably
too large to diffuse easily through the Cu2–xTe structure: their limited diffusion rate restricts their
initial reaction to the surface of the nanocrystals, where cation
exchange is initiated unselectively, leading to core@shell architectures.
Interestingly, these heterostructures were found to be metastable
as they evolved to stable Janus-like architectures if annealed at
200 °C under vacuum.
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Affiliation(s)
- Renyong Tu
- Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy.,Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova , via Dodecaneso, 31, 16146 Genova, Italy
| | - Yi Xie
- Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy.,State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology (WUT) , No. 122, Luoshi Road, Wuhan 430070, PR China
| | - Giovanni Bertoni
- Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy.,IMEM-CNR , Parco Area delle Scienze, 37/A, 43124 Parma, Italy
| | - Aidin Lak
- Drug Discovery and Development, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy
| | - Roberto Gaspari
- CompuNet, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy
| | - Arnaldo Rapallo
- ISMAC - Istituto per lo Studio delle Macromolecole del CNR , via Bassini, 15, 20133 Milano, Italy
| | - Andrea Cavalli
- CompuNet, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy.,Department of Pharmacy and Biotechnology, University of Bologna , via Belmeloro, 6, 40126 Bologna, Italy
| | - Luca De Trizio
- Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy
| | - Liberato Manna
- Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy
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20
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Atomistic understanding of cation exchange in PbS nanocrystals using simulations with pseudoligands. Nat Commun 2016; 7:11503. [PMID: 27160371 PMCID: PMC4866395 DOI: 10.1038/ncomms11503] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 04/05/2016] [Indexed: 11/15/2022] Open
Abstract
Cation exchange is a powerful tool for the synthesis of nanostructures such as core–shell nanocrystals, however, the underlying mechanism is poorly understood. Interactions of cations with ligands and solvent molecules are systematically ignored in simulations. Here, we introduce the concept of pseudoligands to incorporate cation-ligand-solvent interactions in molecular dynamics. This leads to excellent agreement with experimental data on cation exchange of PbS nanocrystals, whereby Pb ions are partially replaced by Cd ions from solution. The temperature and the ligand-type control the exchange rate and equilibrium composition of cations in the nanocrystal. Our simulations reveal that Pb ions are kicked out by exchanged Cd interstitials and migrate through interstitial sites, aided by local relaxations at core–shell interfaces and point defects. We also predict that high-pressure conditions facilitate strongly enhanced cation exchange reactions at elevated temperatures. Our approach is easily extendable to other semiconductor compounds and to other families of nanocrystals. Cation exchange is a promising technique to modify ionic nanostructures by replacing the existing cations with those provided by the solution. Here, the authors use molecular dynamics to study cation exchange in PbS nanocrystals by combining solvent and ligand effects into a pseudoligand parameter.
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21
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Casu A, Genovese A, Manna L, Longo P, Buha J, Botton GA, Lazar S, Kahaly M, Schwingenschloegl U, Prato M, Li H, Ghosh S, Palazon F, De Donato F, Lentijo Mozo S, Zuddas E, Falqui A. Cu₂Se and Cu Nanocrystals as Local Sources of Copper in Thermally Activated In Situ Cation Exchange. ACS NANO 2016; 10:2406-14. [PMID: 26816347 PMCID: PMC4768288 DOI: 10.1021/acsnano.5b07219] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 01/27/2016] [Indexed: 06/05/2023]
Abstract
Among the different synthesis approaches to colloidal nanocrystals, a recently developed toolkit is represented by cation exchange reactions, where the use of template nanocrystals gives access to materials that would be hardly attainable via direct synthesis. Besides, postsynthetic treatments, such as thermally activated solid-state reactions, represent a further flourishing route to promote finely controlled cation exchange. Here, we report that, upon in situ heating in a transmission electron microscope, Cu2Se or Cu nanocrystals deposited on an amorphous solid substrate undergo partial loss of Cu atoms, which are then engaged in local cation exchange reactions with Cu "acceptor" phases represented by rod- and wire-shaped CdSe nanocrystals. This thermal treatment slowly transforms the initial CdSe nanocrystals into Cu(2-x)Se nanocrystals, through the complete sublimation of Cd and the partial sublimation of Se atoms. Both Cu "donor" and "acceptor" particles were not always in direct contact with each other; hence, the gradual transfer of Cu species from Cu2Se or metallic Cu to CdSe nanocrystals was mediated by the substrate and depended on the distance between the donor and acceptor nanostructures. Differently from what happens in the comparably faster cation exchange reactions performed in liquid solution, this study shows that slow cation exchange reactions can be performed at the solid state and helps to shed light on the intermediate steps involved in such reactions.
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Affiliation(s)
- Alberto Casu
- Department
of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
- NABLA Lab, Biological and Environmental Sciences
and Engineering
(BESE) Division and Physical Sciences and Engineering (PSE) Division, King Abdullah University for Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Alessandro Genovese
- Department
of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
- NABLA Lab, Biological and Environmental Sciences
and Engineering
(BESE) Division and Physical Sciences and Engineering (PSE) Division, King Abdullah University for Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Liberato Manna
- Department
of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Paolo Longo
- Gatan,
Inc., 5794 W Las Positas
Boulevard, Pleasanton, California 94588, United States
| | - Joka Buha
- Department
of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Gianluigi A. Botton
- Department
of Materials Science and Engineering, McMaster
University, Hamilton, Ontario L8S 4L8, Canada
| | - Sorin Lazar
- Department
of Materials Science and Engineering, McMaster
University, Hamilton, Ontario L8S 4L8, Canada
- FEI
Electron Optics, Achtseweg
Noord 5, Eindhoven 5600
KA, The Netherlands
| | - Mousumi
Upadhyay Kahaly
- NABLA Lab, Biological and Environmental Sciences
and Engineering
(BESE) Division and Physical Sciences and Engineering (PSE) Division, King Abdullah University for Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Udo Schwingenschloegl
- NABLA Lab, Biological and Environmental Sciences
and Engineering
(BESE) Division and Physical Sciences and Engineering (PSE) Division, King Abdullah University for Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Mirko Prato
- Department
of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Hongbo Li
- Department
of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
- Chemistry
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Sandeep Ghosh
- Department
of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Francisco Palazon
- Department
of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Francesco De Donato
- Department
of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Sergio Lentijo Mozo
- NABLA Lab, Biological and Environmental Sciences
and Engineering
(BESE) Division and Physical Sciences and Engineering (PSE) Division, King Abdullah University for Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Efisio Zuddas
- NABLA Lab, Biological and Environmental Sciences
and Engineering
(BESE) Division and Physical Sciences and Engineering (PSE) Division, King Abdullah University for Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Andrea Falqui
- NABLA Lab, Biological and Environmental Sciences
and Engineering
(BESE) Division and Physical Sciences and Engineering (PSE) Division, King Abdullah University for Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
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22
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Abstract
![]()
Among
the various postsynthesis treatments of colloidal nanocrystals
that have been developed to date, transformations by cation exchange
have recently emerged as an extremely versatile tool that has given
access to a wide variety of materials and nanostructures. One notable
example in this direction is represented by partial cation exchange,
by which preformed nanocrystals can be either transformed to alloy
nanocrystals or to various types of nanoheterostructures possessing
core/shell, segmented, or striped architectures. In this review, we
provide an up to date overview of the complex colloidal nanostructures
that could be prepared so far by cation exchange. At the same time,
the review gives an account of the fundamental thermodynamic and kinetic
parameters governing these types of reactions, as they are currently
understood, and outlines the main open issues and possible future
developments in the field.
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Affiliation(s)
- Luca De Trizio
- Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy
| | - Liberato Manna
- Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego, 30, 16163 Genova, Italy
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23
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Li WF, Fang CM, Dijkstra M, van Huis MA. The role of point defects in PbS, PbSe and PbTe: a first principles study. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:355801. [PMID: 26290521 DOI: 10.1088/0953-8984/27/35/355801] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Intrinsic defects are of central importance to many physical and chemical processes taking place in compound nanomaterials, such as photoluminescence, accommodation of off-stoichiometry and cation exchange. Here, the role of intrinsic defects in the above mentioned processes inside rock salt (RS) lead chalcogenide systems PbS, PbSe and PbTe (PbX) was studied systematically using first principles density functional theory. Vacancy, interstitial, Schottky and Frenkel defects were considered. Rock salt PbO was included for comparison. The studied physical properties include defect formation energy, local geometry relaxation, Bader charge analysis, and electronic structure. The defect formation energies show that monovacancy defects and Schottky defects are favoured over interstitial and Frenkel defects. Schottky dimers, where the cation vacancy and anion vacancy are adjacent to each other, have the lowest defect formation energies at 1.27 eV, 1.29 eV and 1.21 eV for PbS, PbSe and PbTe, respectively. Our results predict that a Pb monovacancy gives rise to a shallow acceptor state, while an X vacancy generates a deep donor state, and Schottky defects create donor-acceptor pairs inside the band gap. The surprisingly low formation energy of Schottky dimers suggests that they may play an important role in cation exchange processes, in contrast to the current notion that only single point defects migrate during cation exchange.
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Affiliation(s)
- Wun-Fan Li
- Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 5, 3584CC Utrecht, The Netherlands
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24
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Zhang J, Chernomordik BD, Crisp RW, Kroupa DM, Luther JM, Miller EM, Gao J, Beard MC. Preparation of Cd/Pb Chalcogenide Heterostructured Janus Particles via Controllable Cation Exchange. ACS NANO 2015; 9:7151-63. [PMID: 26161785 DOI: 10.1021/acsnano.5b01859] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We developed a strategy for producing quasi-spherical nanocrystals of anisotropic heterostructures of Cd/Pb chalcogenides. The nanostructures are fabricated via a controlled cation exchange reaction where the Cd(2+) cation is exchanged for the Pb(2+) cation. The cation exchange reaction is thermally activated and can be controlled by adjusting the reaction temperature or time. We characterized the particles using TEM, XPS, PL, and absorption spectroscopy. With complete exchange, high quality Pb-chalcogenide quantum dots are produced. In addition to Cd(2+), we also find suitable conditions for the exchange of Zn(2+) cations for Pb(2+) cations. The cation exchange is anisotropic starting at one edge of the nanocrystals and proceeds along the ⟨111⟩ direction producing a sharp interface at a (111) crystallographic plane. Instead of spherical core/shell structures, we produced and studied quasi-spherical CdS/PbS and CdSe/PbSe Janus-type heterostructures. Nontrivial PL behavior was observed from the CdS(e)/PbS(e) heterostructures as the Pb:Cd ratio is increased.
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Affiliation(s)
- Jianbing Zhang
- †School of Optical and Electronic Information, Huazhong University of Science and Technology, Hubei 430074, China
- ‡Chemical and Material Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Boris D Chernomordik
- ‡Chemical and Material Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Ryan W Crisp
- ‡Chemical and Material Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
- §Department of Physics, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Daniel M Kroupa
- ‡Chemical and Material Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
- ∥Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, United States
| | - Joseph M Luther
- ‡Chemical and Material Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Elisa M Miller
- ‡Chemical and Material Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Jianbo Gao
- ⊥Center for Advanced Solar Photophysics, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Matthew C Beard
- ‡Chemical and Material Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
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25
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Yalcin AO, Goris B, van Dijk-Moes RJA, Fan Z, Erdamar AK, Tichelaar FD, Vlugt TJH, Van Tendeloo G, Bals S, Vanmaekelbergh D, Zandbergen HW, van Huis MA. Heat-induced transformation of CdSe-CdS-ZnS core-multishell quantum dots by Zn diffusion into inner layers. Chem Commun (Camb) 2015; 51:3320-3. [PMID: 25431813 DOI: 10.1039/c4cc08647c] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work, we investigate the thermal evolution of CdSe-CdS-ZnS core-multishell quantum dots (QDs) in situ using transmission electron microscopy (TEM). Starting at a temperature of approximately 250 °C, Zn diffusion into inner layers takes place together with simultaneous evaporation of particularly Cd and S. As a result of this transformation, CdxZn1-xSe-CdyZn1-yS core-shell QDs are obtained.
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Affiliation(s)
- Anil O Yalcin
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands.
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26
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Kovalenko MV, Manna L, Cabot A, Hens Z, Talapin DV, Kagan CR, Klimov VI, Rogach AL, Reiss P, Milliron DJ, Guyot-Sionnnest P, Konstantatos G, Parak WJ, Hyeon T, Korgel BA, Murray CB, Heiss W. Prospects of nanoscience with nanocrystals. ACS NANO 2015; 9:1012-57. [PMID: 25608730 DOI: 10.1021/nn506223h] [Citation(s) in RCA: 591] [Impact Index Per Article: 65.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Colloidal nanocrystals (NCs, i.e., crystalline nanoparticles) have become an important class of materials with great potential for applications ranging from medicine to electronic and optoelectronic devices. Today's strong research focus on NCs has been prompted by the tremendous progress in their synthesis. Impressively narrow size distributions of just a few percent, rational shape-engineering, compositional modulation, electronic doping, and tailored surface chemistries are now feasible for a broad range of inorganic compounds. The performance of inorganic NC-based photovoltaic and light-emitting devices has become competitive to other state-of-the-art materials. Semiconductor NCs hold unique promise for near- and mid-infrared technologies, where very few semiconductor materials are available. On a purely fundamental side, new insights into NC growth, chemical transformations, and self-organization can be gained from rapidly progressing in situ characterization and direct imaging techniques. New phenomena are constantly being discovered in the photophysics of NCs and in the electronic properties of NC solids. In this Nano Focus, we review the state of the art in research on colloidal NCs focusing on the most recent works published in the last 2 years.
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Affiliation(s)
- Maksym V Kovalenko
- Institute of Inorganic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich , CH-8093 Zürich, Switzerland
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27
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McDowell MT, Lu Z, Koski KJ, Yu JH, Zheng G, Cui Y. In situ observation of divergent phase transformations in individual sulfide nanocrystals. NANO LETTERS 2015; 15:1264-1271. [PMID: 25602713 DOI: 10.1021/nl504436m] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Inorganic nanocrystals have attracted widespread attention both for their size-dependent properties and for their potential use as building blocks in an array of applications. A complete understanding of chemical transformations in nanocrystals is important for controlling structure, composition, and electronic properties. Here, we utilize in situ high-resolution transmission electron microscopy to study structural and morphological transformations in individual sulfide nanocrystals (copper sulfide, iron sulfide, and cobalt sulfide) as they react with lithium. The experiments reveal the influence of structure and composition on the transformation pathway (conversion versus displacement reactions), and they provide a high-resolution view of the unique displacement reaction mechanism in copper sulfide in which copper metal is extruded from the crystal. The structural similarity between the initial and final phases, as well as the mobility of ions within the crystal, are seen to exert a controlling influence on the reaction pathway.
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Affiliation(s)
- Matthew T McDowell
- Department of Materials Science and Engineering, Stanford University , Stanford, California 94305, United States
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28
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Fan Z, Koster RS, Wang S, Fang C, Yalcin AO, Tichelaar FD, Zandbergen HW, van Huis MA, Vlugt TJH. A transferable force field for CdS-CdSe-PbS-PbSe solid systems. J Chem Phys 2014; 141:244503. [DOI: 10.1063/1.4904545] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Zhaochuan Fan
- Process and Energy Department, Delft University of Technology, Leeghwaterstraat 39, 2628 CB Delft,The Netherlands
| | - Rik S. Koster
- Debye Institute for Nanomaterials Science and Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | - Shuaiwei Wang
- Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou, Henan 450006, China
| | - Changming Fang
- Debye Institute for Nanomaterials Science and Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | - Anil O. Yalcin
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands
| | - Frans D. Tichelaar
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands
| | - Henny W. Zandbergen
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands
| | - Marijn A. van Huis
- Debye Institute for Nanomaterials Science and Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | - Thijs J. H. Vlugt
- Process and Energy Department, Delft University of Technology, Leeghwaterstraat 39, 2628 CB Delft,The Netherlands
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