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Guzelturk B, Kamysbayev V, Wang D, Hu H, Li R, King SB, Reid AH, Lin MF, Wang X, Walko DA, Zhang X, Lindenberg A, Talapin DV. Understanding and Controlling Photothermal Responses in MXenes. Nano Lett 2023; 23:2677-2686. [PMID: 36917456 DOI: 10.1021/acs.nanolett.2c05001] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
MXenes have the potential for efficient light-to-heat conversion in photothermal applications. To effectively utilize MXenes in such applications, it is important to understand the underlying nonequilibrium processes, including electron-phonon and phonon-phonon couplings. Here, we use transient electron and X-ray diffraction to investigate the heating and cooling of photoexcited MXenes at femtosecond to nanosecond time scales. Our results show extremely strong electron-phonon coupling in Ti3C2-based MXenes, resulting in lattice heating within a few hundred femtoseconds. We also systematically study heat dissipation in MXenes with varying film thicknesses, chemical surface terminations, flake sizes, and annealing conditions. We find that the thermal boundary conductance (TBC) governs the thermal relaxation in films thinner than the optical penetration depth. We achieve a 2-fold enhancement of the TBC, reaching 20 MW m-2 K-1, by controlling the flake size or chemical surface termination, which is promising for engineering heat dissipation in photothermal and thermoelectric applications of the MXenes.
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Affiliation(s)
- Burak Guzelturk
- X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Vladislav Kamysbayev
- Department of Chemistry, James Franck Institute, and Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Di Wang
- Department of Chemistry, James Franck Institute, and Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Huicheng Hu
- Department of Chemistry, James Franck Institute, and Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Ruiyu Li
- Department of Chemistry, James Franck Institute, and Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Sarah B King
- Department of Chemistry, James Franck Institute, and Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Alexander H Reid
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Ming-Fu Lin
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Xijie Wang
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Donald A Walko
- X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Xiaoyi Zhang
- X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Aaron Lindenberg
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Dmitri V Talapin
- Department of Chemistry, James Franck Institute, and Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States
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2
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Kamysbayev V, Filatov AS, Hu H, Rui X, Lagunas F, Wang D, Klie RF, Talapin DV. Covalent surface modifications and superconductivity of two-dimensional metal
carbide MXenes. Science 2020; 369:979-983. [DOI: 10.1126/science.aba8311] [Citation(s) in RCA: 421] [Impact Index Per Article: 105.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 06/02/2020] [Indexed: 12/17/2022]
Abstract
Versatile chemical transformations of surface functional groups in
two-dimensional transition-metal carbides (MXenes) open up a previously unexplored
design space for this broad class of functional materials. We introduce a general
strategy to install and remove surface groups by performing substitution and
elimination reactions in molten inorganic salts. Successful synthesis of MXenes
with oxygen, imido, sulfur, chlorine, selenium, bromine, and tellurium surface
terminations, as well as bare MXenes (no surface termination), was demonstrated.
These MXenes show distinctive structural and electronic properties. For example,
the surface groups control interatomic distances in the MXene lattice, and
Tin+1Cn
(n = 1, 2) MXenes terminated with telluride
(Te2−) ligands show a giant (>18%) in-plane lattice
expansion compared with the unstrained titanium carbide lattice. The surface
groups also control superconductivity of niobium carbide MXenes.
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Affiliation(s)
- Vladislav Kamysbayev
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, IL 60637, USA
| | - Alexander S. Filatov
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, IL 60637, USA
| | - Huicheng Hu
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, IL 60637, USA
| | - Xue Rui
- Department of Physics, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Francisco Lagunas
- Department of Physics, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Di Wang
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, IL 60637, USA
| | - Robert F. Klie
- Department of Physics, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Dmitri V. Talapin
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, IL 60637, USA
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, IL 60439, USA
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3
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Diroll BT, Kamysbayev V, Coropceanu I, Talapin DV, Schaller RD. Heat-driven acoustic phonons in lamellar nanoplatelet assemblies. Nanoscale 2020; 12:9661-9668. [PMID: 32319509 DOI: 10.1039/d0nr00695e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Colloidal CdSe nanoplatelets, with the electronic structure of quantum wells, self-assemble into lamellar stacks due to large co-facial van der Waals attractions. These lamellar stacks are shown to display coherent acoustic phonons that are detected from oscillatory changes in the absorption spectrum observed in infrared pump, electronic probe measurements. Rather than direct electronic excitation of the nanocrystals using a femtosecond laser, impulsive transfer of heat from the organic ligand shell, excited at C-H stretching vibrational resonances, to the inorganic core of individual nanoplatelets occurs on a time-scale of <100 ps. This heat transfer drives in-phase longitudinal acoustic phonons of the nanoplatelet lamellae, which are accompanied by subtle deformations along the nanoplatelet short axes. The frequencies of the oscillations vary from 0.7 to 2 GHz (3-8 μeV and 0.5-1 ns oscillation period) depending on the thickness of the nanoplatelets-but not their lateral areas-and the temperature of the sample. Temperature-dependence of the acoustic phonon frequency conveys a substantial stiffening of the organic ligand bonds between nanoplatelets with reduced temperature. These results demonstrate a potential for acoustic modulation of the excitonic structure of nanocrystal assemblies in self-assembled anisotropic semiconductor systems at temperatures at or above 300 K.
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Affiliation(s)
- Benjamin T Diroll
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, IL 60439, USA.
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4
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Guzelturk B, Utterback JK, Coropceanu I, Kamysbayev V, Janke EM, Zajac M, Yazdani N, Cotts BL, Park S, Sood A, Lin MF, Reid AH, Kozina ME, Shen X, Weathersby SP, Wood V, Salleo A, Wang X, Talapin DV, Ginsberg NS, Lindenberg AM. Nonequilibrium Thermodynamics of Colloidal Gold Nanocrystals Monitored by Ultrafast Electron Diffraction and Optical Scattering Microscopy. ACS Nano 2020; 14:4792-4804. [PMID: 32208676 DOI: 10.1021/acsnano.0c00673] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Metal nanocrystals exhibit important optoelectronic and photocatalytic functionalities in response to light. These dynamic energy conversion processes have been commonly studied by transient optical probes to date, but an understanding of the atomistic response following photoexcitation has remained elusive. Here, we use femtosecond resolution electron diffraction to investigate transient lattice responses in optically excited colloidal gold nanocrystals, revealing the effects of nanocrystal size and surface ligands on the electron-phonon coupling and thermal relaxation dynamics. First, we uncover a strong size effect on the electron-phonon coupling, which arises from reduced dielectric screening at the nanocrystal surfaces and prevails independent of the optical excitation mechanism (i.e., inter- and intraband). Second, we find that surface ligands act as a tuning parameter for hot carrier cooling. Particularly, gold nanocrystals with thiol-based ligands show significantly slower carrier cooling as compared to amine-based ligands under intraband optical excitation due to electronic coupling at the nanocrystal/ligand interfaces. Finally, we spatiotemporally resolve thermal transport and heat dissipation in photoexcited nanocrystal films by combining electron diffraction with stroboscopic elastic scattering microscopy. Taken together, we resolve the distinct thermal relaxation time scales ranging from 1 ps to 100 ns associated with the multiple interfaces through which heat flows at the nanoscale. Our findings provide insights into optimization of gold nanocrystals and their thin films for photocatalysis and thermoelectric applications.
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Affiliation(s)
- Burak Guzelturk
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025 United States
| | - James K Utterback
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Igor Coropceanu
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, Illinois 60637, United States
| | - Vladislav Kamysbayev
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, Illinois 60637, United States
| | - Eric M Janke
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, Illinois 60637, United States
| | - Marc Zajac
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
| | - Nuri Yazdani
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025 United States
- Department of Information Technology and Electrical Engineering, ETH Zurich, 8092 Zurich, Switzerland
| | - Benjamin L Cotts
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
| | - Suji Park
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025 United States
| | - Aditya Sood
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025 United States
| | - Ming-Fu Lin
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Alexander H Reid
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Michael E Kozina
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Xiaozhe Shen
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Stephen P Weathersby
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Vanessa Wood
- Department of Information Technology and Electrical Engineering, ETH Zurich, 8092 Zurich, Switzerland
| | - Alberto Salleo
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
| | - Xijie Wang
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Dmitri V Talapin
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, Illinois 60637, United States
| | - Naomi S Ginsberg
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Department of Physics, University of California, Berkeley, California 94720, United States
- Molecular Biophysics and Integrated Bioimaging Division and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Kavli Energy NanoSciences Institute, Berkeley, California 94720, United States
| | - Aaron M Lindenberg
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025 United States
- The PULSE Institute for Ultrafast Energy Science, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Department of Photon Science, Stanford University and SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
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5
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Lan X, Chen M, Hudson MH, Kamysbayev V, Wang Y, Guyot-Sionnest P, Talapin DV. Quantum dot solids showing state-resolved band-like transport. Nat Mater 2020; 19:323-329. [PMID: 31988516 DOI: 10.1038/s41563-019-0582-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 12/11/2019] [Indexed: 06/10/2023]
Abstract
Improving charge mobility in quantum dot (QD) films is important for the performance of photodetectors, solar cells and light-emitting diodes. However, these applications also require preservation of well defined QD electronic states and optical transitions. Here, we present HgTe QD films that show high mobility for charges transported through discrete QD states. A hybrid surface passivation process efficiently eliminates surface states, provides tunable air-stable n and p doping and enables hysteresis-free filling of QD states evidenced by strong conductance modulation. QD films dried at room temperature without any post-treatments exhibit mobility up to μ ~ 8 cm2 V-1 s-1 at a low carrier density of less than one electron per QD, band-like behaviour down to 77 K, and similar drift and Hall mobilities at all temperatures. This unprecedented set of electronic properties raises important questions about the delocalization and hopping mechanisms for transport in QD solids, and introduces opportunities for improving QD technologies.
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Affiliation(s)
- Xinzheng Lan
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, IL, USA
| | - Menglu Chen
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, IL, USA
| | - Margaret H Hudson
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, IL, USA
| | - Vladislav Kamysbayev
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, IL, USA
| | - Yuanyuan Wang
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, IL, USA
| | - Philippe Guyot-Sionnest
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, IL, USA.
| | - Dmitri V Talapin
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, IL, USA.
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6
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Kamysbayev V, James NM, Filatov AS, Srivastava V, Anasori B, Jaeger HM, Gogotsi Y, Talapin DV. Colloidal Gelation in Liquid Metals Enables Functional Nanocomposites of 2D Metal Carbides (MXenes) and Lightweight Metals. ACS Nano 2019; 13:12415-12424. [PMID: 31560851 DOI: 10.1021/acsnano.9b06207] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Nanomaterials dispersed in different media, such as liquids or polymers, generate a variety of functional composites with synergistic properties. In this work, we discuss liquid metals as the nanomaterials' dispersion media. For example, 2D transition-metal carbides and nitrides (MXenes) can be efficiently dispersed in liquid Ga and lightweight alloys of Al, Mg, and Li. We show that the Lifshitz theory predicts strong van der Waals attraction between nanoscale objects interacting through liquid metals. However, a uniform distribution of MXenes in liquid metals can be achieved through colloidal gelation, where particles form self-supporting networks stable against macroscopic phase segregation. This network acts as a reinforcement boosting mechanical properties of the resulting metal-matrix composite. By choosing Mg-Li alloy as an example of ultralightweight metal matrix and Ti3C2Tx MXene as a nanoscale reinforcement, we apply a liquid metal gelation technique to fabricate functional nanocomposites with an up to 57% increase in the specific yield strength without compromising the matrix alloy's plasticity. MXenes largely retain their phase and 2D morphology after processing in liquid Mg-Li alloy at 700 °C. The 2D morphology enables formation of a strong semicoherent interface between MXene and metal matrix, manifested by biaxial strain of the MXene lattice inside the metal matrix. This work expands applications for MXenes and shows the potential for developing MXene-reinforced metal matrix composites for structural alloys and other emerging applications with metal-MXene interfaces, such as batteries and supercapacitors.
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Affiliation(s)
- Vladislav Kamysbayev
- Department of Chemistry and James Franck Institute , University of Chicago , Chicago , Illinois 60637 , United States
| | - Nicole M James
- Department of Chemistry and James Franck Institute , University of Chicago , Chicago , Illinois 60637 , United States
| | - Alexander S Filatov
- Department of Chemistry and James Franck Institute , University of Chicago , Chicago , Illinois 60637 , United States
| | - Vishwas Srivastava
- Department of Chemistry and James Franck Institute , University of Chicago , Chicago , Illinois 60637 , United States
| | - Babak Anasori
- A. J. Drexel Nanomaterials Institute and Department of Materials Science and Engineering , Drexel University , Philadelphia , Pennsylvania 19104 , United States
| | - Heinrich M Jaeger
- Department of Physics and James Franck Institute , University of Chicago , Chicago , Illinois 60637 , United States
| | - Yury Gogotsi
- A. J. Drexel Nanomaterials Institute and Department of Materials Science and Engineering , Drexel University , Philadelphia , Pennsylvania 19104 , United States
| | - Dmitri V Talapin
- Department of Chemistry and James Franck Institute , University of Chicago , Chicago , Illinois 60637 , United States
- Center for Nanoscale Materials , Argonne National Laboratory , Argonne , Illinois 60439 , United States
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7
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Kamysbayev V, Srivastava V, Ludwig NB, Borkiewicz OJ, Zhang H, Ilavsky J, Lee B, Chapman KW, Vaikuntanathan S, Talapin DV. Nanocrystals in Molten Salts and Ionic Liquids: Experimental Observation of Ionic Correlations Extending beyond the Debye Length. ACS Nano 2019; 13:5760-5770. [PMID: 30964280 DOI: 10.1021/acsnano.9b01292] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The nature of the interface between the solute and the solvent in a colloidal solution has attracted attention for a long time. For example, the surface of colloidal nanocrystals (NCs) is specially designed to impart colloidal stability in a variety of polar and nonpolar solvents. This work focuses on a special type of colloids where the solvent is a molten inorganic salt or organic ionic liquid. The stability of such colloids is hard to rationalize because solvents with high density of mobile charges efficiently screen the electrostatic double-layer repulsion, and purely ionic molten salts represent an extreme case where the Debye length is only ∼1 Å. We present a detailed investigation of NC dispersions in molten salts and ionic liquids using small-angle X-ray scattering (SAXS), atomic pair distribution function (PDF) analysis and molecular dynamics (MD) simulations. Our SAXS analysis confirms that a wide variety of NCs (Pt, CdSe/CdS, InP, InAs, ZrO2) can be uniformly dispersed in molten salts like AlCl3/NaCl/KCl (AlCl3/AlCl4-) and NaSCN/KSCN and in ionic liquids like 1-butyl-3-methylimidazolium halides (BMIM+X-, where X = Cl, Br, I). By using a combination of PDF analysis and molecular modeling, we demonstrate that the NC surface induces a solvent restructuring with electrostatic correlations extending an order of magnitude beyond the Debye screening length. These strong oscillatory ion-ion correlations, which are not accounted by the traditional mechanisms of steric and electrostatic stabilization of colloids, offer additional insight into solvent-solute interactions and enable apparently "impossible" colloidal stabilization in highly ionized media.
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Affiliation(s)
- Vladislav Kamysbayev
- Department of Chemistry and James Franck Institute , University of Chicago , Chicago , Illinois 60637 , United States
| | - Vishwas Srivastava
- Department of Chemistry and James Franck Institute , University of Chicago , Chicago , Illinois 60637 , United States
| | - Nicholas B Ludwig
- Department of Chemistry and James Franck Institute , University of Chicago , Chicago , Illinois 60637 , United States
| | - Olaf J Borkiewicz
- X-ray Science Division, Advanced Photon Source , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | - Hao Zhang
- Department of Chemistry and James Franck Institute , University of Chicago , Chicago , Illinois 60637 , United States
| | - Jan Ilavsky
- X-ray Science Division, Advanced Photon Source , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | - Byeongdu Lee
- X-ray Science Division, Advanced Photon Source , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | - Karena W Chapman
- X-ray Science Division, Advanced Photon Source , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | | | - Dmitri V Talapin
- Department of Chemistry and James Franck Institute , University of Chicago , Chicago , Illinois 60637 , United States
- Center for Nanoscale Materials , Argonne National Laboratory , Argonne , Illinois 60439 , United States
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8
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Hudson MH, Chen M, Kamysbayev V, Janke EM, Lan X, Allan G, Delerue C, Lee B, Guyot-Sionnest P, Talapin DV. Conduction Band Fine Structure in Colloidal HgTe Quantum Dots. ACS Nano 2018; 12:9397-9404. [PMID: 30125488 DOI: 10.1021/acsnano.8b04539] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
HgTe colloidal quantum dots (QDs) are of interest because quantum confinement of semimetallic bulk HgTe allows one to synthetically control the bandgap throughout the infrared. Here, we synthesize highly monodisperse HgTe QDs and tune their doping both chemically and electrochemically. The monodispersity of the QDs was evaluated using small-angle X-ray scattering (SAXS) and suggests a diameter distribution of ∼10% across multiple batches of different sizes. Electron-doped HgTe QDs display an intraband absorbance and bleaching of the first two excitonic features. We see splitting of the intraband peaks corresponding to electronic transitions from the occupied 1Se state to a series of nondegenerate 1Pe states. Spectroelectrochemical studies reveal that the degree of splitting and relative intensity of the intraband features remain constant across doping levels up to two electrons per QD. Theoretical modeling suggests that the splitting of the 1Pe level arises from spin-orbit coupling and reduced QD symmetry. The fine structure of the intraband transitions is observed in the ensemble studies due to the size uniformity of the as-synthesized QDs and strong spin-orbit coupling inherent to HgTe.
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Affiliation(s)
| | | | | | | | | | - Guy Allan
- University of Lille, CNRS, Centrale Lille, ISEN, University of Valenciennes , UMR 8520 - IEMN, F-59000 Lille , France
| | - Christophe Delerue
- University of Lille, CNRS, Centrale Lille, ISEN, University of Valenciennes , UMR 8520 - IEMN, F-59000 Lille , France
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9
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Srivastava V, Kamysbayev V, Hong L, Dunietz E, Klie RF, Talapin DV. Colloidal Chemistry in Molten Salts: Synthesis of Luminescent In1–xGaxP and In1–xGaxAs Quantum Dots. J Am Chem Soc 2018; 140:12144-12151. [DOI: 10.1021/jacs.8b06971] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Vishwas Srivastava
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, Illinois 60637, United States
| | - Vladislav Kamysbayev
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, Illinois 60637, United States
| | - Liang Hong
- Department of Physics, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Eleanor Dunietz
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, Illinois 60637, United States
| | - Robert F. Klie
- Department of Physics, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Dmitri V. Talapin
- Department of Chemistry and James Franck Institute, University of Chicago, Chicago, Illinois 60637, United States
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, United States
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10
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Srivastava V, Liu W, Janke EM, Kamysbayev V, Filatov AS, Sun CJ, Lee B, Rajh T, Schaller RD, Talapin DV. Understanding and Curing Structural Defects in Colloidal GaAs Nanocrystals. Nano Lett 2017; 17:2094-2101. [PMID: 28191964 DOI: 10.1021/acs.nanolett.7b00481] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
GaAs is one of the most important semiconductors. However, colloidal GaAs nanocrystals remain largely unexplored because of the difficulties with their synthesis. Traditional synthetic routes either fail to produce pure GaAs phase or result in materials whose optical properties are very different from the behavior expected for quantum dots of direct-gap semiconductors. In this work, we demonstrate a variety of synthetic routes toward crystalline GaAs NCs. By using a combination of Raman, EXAFS, transient absorption, and EPR spectroscopies, we conclude that unusual optical properties of colloidal GaAs NCs can be related to the presence of Ga vacancies and lattice disorder. These defects do not manifest themselves in TEM images and powder X-ray diffraction patterns but are responsible for the lack of absorption features even in apparently crystalline GaAs nanoparticles. We introduce a novel molten salt based annealing approach to alleviate these structural defects and show the emergence of size-dependent excitonic transitions in colloidal GaAs quantum dots.
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Affiliation(s)
- Vishwas Srivastava
- Department of Chemistry and James Franck Institute, University of Chicago , Chicago, Illinois 60637, United States
| | - Wenyong Liu
- Department of Chemistry and James Franck Institute, University of Chicago , Chicago, Illinois 60637, United States
| | - Eric M Janke
- Department of Chemistry and James Franck Institute, University of Chicago , Chicago, Illinois 60637, United States
| | - Vladislav Kamysbayev
- Department of Chemistry and James Franck Institute, University of Chicago , Chicago, Illinois 60637, United States
| | - Alexander S Filatov
- Department of Chemistry and James Franck Institute, University of Chicago , Chicago, Illinois 60637, United States
| | - Cheng-Jun Sun
- Advanced Photon Source, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Byeongdu Lee
- Advanced Photon Source, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Tijana Rajh
- Center for Nanoscale Materials, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Richard D Schaller
- Center for Nanoscale Materials, Argonne National Laboratory , Argonne, Illinois 60439, United States
- Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States
| | - Dmitri V Talapin
- Department of Chemistry and James Franck Institute, University of Chicago , Chicago, Illinois 60637, United States
- Center for Nanoscale Materials, Argonne National Laboratory , Argonne, Illinois 60439, United States
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