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Luo Y, Yang H, Ying C, Wang R, Bo Z, Yan J, Cen K, Ostrikov KK. Plasma-Activated Solutions Regulate Surface-Terminating Groups Enhancing Pseudocapacitive Ti 3 C 2 T x Electrode Performance. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2305383. [PMID: 37661349 DOI: 10.1002/smll.202305383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 08/09/2023] [Indexed: 09/05/2023]
Abstract
2D transition metal carbides and nitrides (MXenes) are actively pursued as pseudocapacitive materials for supercapacitors owing to their advantages in electronic conductivity and surface reactivity. Increasing the fraction of ─O terminal groups in Ti3 C2 Tx is a promising approach to improve the pseudocapacitive charge storage in H2 SO4 electrolytes, but it suffers from a lack of effective functionalization methods and stability of the groups in practical operation. Here a low-temperature and environment-friendly approach via the interaction of nonequilibrium plasmas with Ti3 C2 Tx dispersion is demonstrated to generate abundant and stable surface-terminating O groups. The impact of the discharge environment (Ar, O2 , and H2 ) on the structural characteristics and electrochemical performance of Ti3 C2 Tx nanosheets is studied. The Ti3 C2 Tx modified in Ar and H2 maintains their original morphology but a significantly lower F content. Consequently, an extraordinarily high content (78.5%) of surface-terminating O groups is revealed by the high-resolution X-ray photoelectron spectroscopy spectra for the Ti3 C2 Tx samples modified in H2 plasma-treated solutions. Additionally, the Ti3 C2 Tx treated using H2 plasmas exhibits the best capacitive performance of 418.3 F g-1 at 2 mV s-1 , which can maintain 95.88% capacity after 10 000 cycles. These results contribute to the development of advanced nanostructured pseudocapacitive electrode materials for renewable energy storage applications.
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Affiliation(s)
- Yonghong Luo
- State Key Laboratory of Clean Energy Utilization, College of Energy Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Huachao Yang
- State Key Laboratory of Clean Energy Utilization, College of Energy Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Chongyan Ying
- State Key Laboratory of Clean Energy Utilization, College of Energy Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Rui Wang
- State Key Laboratory of Clean Energy Utilization, College of Energy Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Zheng Bo
- State Key Laboratory of Clean Energy Utilization, College of Energy Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Jianhua Yan
- State Key Laboratory of Clean Energy Utilization, College of Energy Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Kefa Cen
- State Key Laboratory of Clean Energy Utilization, College of Energy Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Kostya Ken Ostrikov
- School of Chemistry and Physics & Centre for Materials Science, Queensland University of Technology, Brisbane, Queensland, 4000, Australia
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2
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Dunlap MK, Ryan DP, Goodwin PM, Sheehan CJ, Werner JH, Majumder S, Hollingsworth JA, Gelfand MP, Van Orden A. Nanoscale imaging of quantum dot dimers using time-resolved super-resolution microscopy combined with scanning electron microscopy. NANOTECHNOLOGY 2023; 34:275202. [PMID: 37011598 DOI: 10.1088/1361-6528/acc9c9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 04/03/2023] [Indexed: 06/19/2023]
Abstract
Time-resolved super-resolution microscopy was used in conjunction with scanning electron microscopy to image individual colloidal CdSe/CdS semiconductor quantum dots (QD) and QD dimers. The photoluminescence (PL) lifetimes, intensities, and structural parameters were acquired with nanometer scale spatial resolution and sub-nanosecond time resolution. The combination of these two techniques was more powerful than either alone, enabling us to resolve the PL properties of individual QDs within QD dimers as they blinked on and off, measure interparticle distances, and identify QDs that may be participating in energy transfer. The localization precision of our optical imaging technique was ∼3 nm, low enough that the emission from individual QDs within the dimers could be spatially resolved. While the majority of QDs within dimers acted as independent emitters, at least one pair of QDs in our study exhibited lifetime and intensity behaviors consistent with resonance energy transfer from a shorter lifetime and lower intensity donor QD to a longer lifetime and higher intensity acceptor QD. For this case, we demonstrate how the combined super-resolution optical imaging and scanning electron microscopy data can be used to characterize the energy transfer rate.
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Affiliation(s)
- Megan K Dunlap
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, United States of America
| | - Duncan P Ryan
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545, United States of America
| | - Peter M Goodwin
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545, United States of America
| | - Chris J Sheehan
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545, United States of America
| | - James H Werner
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545, United States of America
| | - Somak Majumder
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545, United States of America
| | - Jennifer A Hollingsworth
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545, United States of America
| | - Martin P Gelfand
- Department of Physics, Colorado State University, Fort Collins, CO 80523-1872, United States of America
| | - Alan Van Orden
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, United States of America
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3
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Pringle TA, Hunter KI, Brumberg A, Anderson KJ, Fagan JA, Thomas SA, Petersen RJ, Sefannaser M, Han Y, Brown SL, Kilin DS, Schaller RD, Kortshagen UR, Boudjouk PR, Hobbie EK. Bright Silicon Nanocrystals from a Liquid Precursor: Quasi-Direct Recombination with High Quantum Yield. ACS NANO 2020; 14:3858-3867. [PMID: 32150383 DOI: 10.1021/acsnano.9b09614] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Silicon nanocrystals (SiNCs) with bright bandgap photoluminescence (PL) are of current interest for a range of potential applications, from solar windows to biomedical contrast agents. Here, we use the liquid precursor cyclohexasilane (Si6H12) for the plasma synthesis of colloidal SiNCs with exemplary core emission. Through size separation executed in an oxygen-shielded environment, we achieve PL quantum yields (QYs) approaching 70% while exposing intrinsic constraints on efficient core emission from smaller SiNCs. Time-resolved PL spectra of these fractions in response to femtosecond pulsed excitation reveal a zero-phonon radiative channel that anticorrelates with QY, which we model using advanced computational methods applied to a 2 nm SiNC. Our results offer additional insight into the photophysical interplay of the nanocrystal surface, quasi-direct recombination, and efficient SiNC core PL.
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Affiliation(s)
- Todd A Pringle
- Materials and Nanotechnology Program, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Katharine I Hunter
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Alexandra Brumberg
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Kenneth J Anderson
- Department of Chemistry & Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Jeffrey A Fagan
- National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Salim A Thomas
- Materials and Nanotechnology Program, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Reed J Petersen
- Department of Physics, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Mahmud Sefannaser
- Department of Physics, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Yulun Han
- Department of Chemistry & Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Samuel L Brown
- Materials and Nanotechnology Program, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Dmitri S Kilin
- Department of Chemistry & Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Richard D Schaller
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Uwe R Kortshagen
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Philip Raymond Boudjouk
- Department of Chemistry & Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Erik K Hobbie
- Materials and Nanotechnology Program, North Dakota State University, Fargo, North Dakota 58108, United States
- Department of Physics, North Dakota State University, Fargo, North Dakota 58108, United States
- Department of Coatings and Polymeric Materials, North Dakota State University, Fargo, North Dakota 58108, United States
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4
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Kim DY, Kim HV, Kang J. In Situ Synthesis of Silicon-Carbon Composites and Application as Lithium-Ion Battery Anode Materials. MATERIALS 2019; 12:ma12182871. [PMID: 31492003 PMCID: PMC6765966 DOI: 10.3390/ma12182871] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 08/28/2019] [Accepted: 09/03/2019] [Indexed: 11/16/2022]
Abstract
Silicon can be used in a variety of applications. Particularly, silicon particles are attracting increased attention as energy storage materials for lithium-ion batteries. However, silicon has a limited cycling performance owing to its peeling from the current collector and the volume expansion that occurs during alloying with lithium in the charging process. Significant contributors to this problem are the even distribution of silicon nanoparticles within the carbon matrix and their deep placement in the internal structure. In this study, we synthesized silicon nanoparticles and carbon materials via a bottom-up approach using a new method called plasma in solution. Silicon nanoparticles and the carbon matrix were synthesized in a structure similar to carbon black. It was confirmed that the silicon particles were evenly distributed in the carbon matrix. In addition, the evaluation of the electrochemical performance of the silicon-carbon matrix (Si-C) composite material showed that it exhibited stable cycling performance with high reversible capacity.
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Affiliation(s)
- Dae-Yeong Kim
- Division of Marine Engineering, Korea Maritime and Ocean University, 727 Taejong-ro, Yeongdo-gu, Busan 49112, Korea.
| | - Han-Vin Kim
- Department of Electrical and Electronic Engineering, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
| | - Jun Kang
- Division of Marine Engineering, Korea Maritime and Ocean University, 727 Taejong-ro, Yeongdo-gu, Busan 49112, Korea.
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5
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Jakob M, Javadi M, Veinot JGC, Meldrum A, Kartouzian A, Heiz U. Ensemble Effects in the Temperature-Dependent Photoluminescence of Silicon Nanocrystals. Chemistry 2019; 25:3061-3067. [DOI: 10.1002/chem.201804986] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 12/14/2018] [Indexed: 01/10/2023]
Affiliation(s)
- Matthias Jakob
- Chair of Physical Chemistry; Technical University of Munich; Lichtenbergstrasse 4 85748 Garching Germany
| | - Morteza Javadi
- Department of Chemistry; University of Alberta; T6G 2R3 Edmonton Alberta Canada
| | | | - Al Meldrum
- Department of Physics; University of Alberta; T6G 2E1 Edmonton Alberta Canada
| | - Aras Kartouzian
- Chair of Physical Chemistry; Technical University of Munich; Lichtenbergstrasse 4 85748 Garching Germany
| | - Ulrich Heiz
- Chair of Physical Chemistry; Technical University of Munich; Lichtenbergstrasse 4 85748 Garching Germany
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6
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Cai Q, Meng H, Liu Y, Li Z. Fluorometric determination of glucose based on a redox reaction between glucose and aminopropyltriethoxysilane and in-situ formation of blue-green emitting silicon nanodots. Mikrochim Acta 2019; 186:78. [PMID: 30627875 DOI: 10.1007/s00604-018-3189-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 12/14/2018] [Indexed: 12/17/2022]
Abstract
A method is described for fluorometric detection of glucose. It is based on the finding that silicon nanodots (SNDs) are formed from glucose and aminopropyltriethoxysilane (APTES) under mild experimental conditions. The SNDs thus formed have an average diameter of ∼2 nm, exhibit good water dispersibility, blue fluorescence (with excitation/emission maxima at 410/475 nm), broad pH tolerance, and are photostable. The assay was applied to the quantification of glucose with high sensitivity, good specificity, and over a wide detection range (from 10 μM to 0.9 mM). It was applied to the determination of glucose in spiked serum samples and gave satisfactory results and recoveries. Graphical abstract Schematic presentation of serum glucose detection based on a redox reaction between glucose and aminopropyltriethoxysilane and in-situ formation of blue-green emitting silicon nanodots.
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Affiliation(s)
- Qiyong Cai
- Institute of Chemical Biology and Nanomedicine (ICBN), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, People's Republic of China.
| | - Hongmin Meng
- College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, 450001, People's Republic of China
| | - Yeru Liu
- Institute of Chemical Biology and Nanomedicine (ICBN), State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, People's Republic of China
| | - Zhaohui Li
- College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, 450001, People's Republic of China.
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7
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Angı A, Sinelnikov R, Heenen HH, Meldrum A, Veinot JGC, Scheurer C, Reuter K, Ashkenazy O, Azulay D, Balberg I, Millo O, Rieger B. The influence of conjugated alkynyl(aryl) surface groups on the optical properties of silicon nanocrystals: photoluminescence through in-gap states. NANOTECHNOLOGY 2018; 29:355705. [PMID: 29862985 DOI: 10.1088/1361-6528/aac9ef] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Developing new methods, other than size and shape, for controlling the optoelectronic properties of semiconductor nanocrystals is a highly desired target. Here we demonstrate that the photoluminescence (PL) of silicon nanocrystals (SiNCs) can be tuned in the range 685-800 nm solely via surface functionalization with alkynyl(aryl) (phenylacetylene, 2-ethynylnaphthalene, 2-ethynyl-5-hexylthiophene) surface groups. Scanning tunneling microscopy/spectroscopy on single nanocrystals revealed the formation of new in-gap states adjacent to the conduction band edge of the functionalized SiNCs. PL red-shifts were attributed to emission through these in-gap states, which reduce the effective band gap for the electron-hole recombination process. The observed in-gap states can be associated with new interface states formed via (-Si-C≡C-) bonds in combination with conjugated molecules as indicated by ab initio calculations. In contrast to alkynyl(aryl)s, the formation of in-gap states and shifts in PL maximum of the SiNCs were not observed with aryl (phenyl, naphthalene, 2-hexylthiophene) and alkynyl (1-dodecyne) surface groups. These outcomes show that surface functionalization with alkynyl(aryl) molecules is a valuable tool to control the electronic structure and optical properties of SiNCs via tuneable interface states, which may enhance the performance of SiNCs in semiconductor devices.
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Affiliation(s)
- Arzu Angı
- WACKER-Lehrstuhl für Makromolekulare Chemie, Technische Universität München, Lichtenbergstraße 4, D-85747, Germany. Catalysis Research Center, Ernst-Otto-Fischer-Straße 1, D-85748 Garching, Germany
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8
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Han Y, Anderson K, Hobbie EK, Boudjouk P, Kilin DS. Unraveling Photodimerization of Cyclohexasilane from Molecular Dynamics Studies. J Phys Chem Lett 2018; 9:4349-4354. [PMID: 30004709 DOI: 10.1021/acs.jpclett.8b01691] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Photoinduced reactions of a pair of cyclohexasilane (CHS) monomers are explored by time-dependent excited-state molecular dynamics (TDESMD) calculations. In TDESMD trajectories, one observes vivid reaction events including dimerization and fragmentation. A general reaction pathway is identified as (i) ring-opening formation of a dimer, (ii) rearrangement induced by bond breaking, and (iii) decomposition through the elimination of small fragments. The identified pathway supports the chemistry proposed for the fabrication of silicon-based materials using CHS as a precursor. In addition, we find dimers have smaller HOMO-LUMO gaps and exhibit a red shift and line-width broadening in the computed photoluminescence spectra compared with a pair of CHS monomers.
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Affiliation(s)
- Yulun Han
- Department of Chemistry and Biochemistry , North Dakota State University , Fargo , North Dakota 58102 , United States
| | - Kenneth Anderson
- Department of Chemistry and Biochemistry , North Dakota State University , Fargo , North Dakota 58102 , United States
| | - Erik K Hobbie
- Department of Chemistry and Biochemistry , North Dakota State University , Fargo , North Dakota 58102 , United States
| | - Philip Boudjouk
- Department of Chemistry and Biochemistry , North Dakota State University , Fargo , North Dakota 58102 , United States
| | - Dmitri S Kilin
- Department of Chemistry and Biochemistry , North Dakota State University , Fargo , North Dakota 58102 , United States
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9
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Marinins A, Zandi Shafagh R, van der Wijngaart W, Haraldsson T, Linnros J, Veinot JGC, Popov S, Sychugov I. Light-Converting Polymer/Si Nanocrystal Composites with Stable 60-70% Quantum Efficiency and Their Glass Laminates. ACS APPLIED MATERIALS & INTERFACES 2017; 9:30267-30272. [PMID: 28853276 DOI: 10.1021/acsami.7b09265] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Thiol-ene polymer/Si nanocrystal bulk hybrids were synthesized from alkyl-passivated Si nanocrystal (Si NC) toluene solutions. Radicals in the polymer provided a copassivation of "dark" Si NCs, making them optically active and leading to a substantial ensemble quantum yield increase. Optical stability over several months was confirmed. The presented materials exhibit the highest photoluminescence quantum yield (∼65%) of any solid-state Si NC hybrid reported to date. The broad tunability of thiol-ene polymer reactivity provides facile glass integration, as demonstrated by a laminated structure. This, together with extremely fast polymerization, makes the demonstrated hybrid material a promising candidate for light converting applications.
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Affiliation(s)
- Aleksandrs Marinins
- Department of Applied Physics, KTH - Royal Institute of Technology , 16440 Stockholm, Sweden
| | - Reza Zandi Shafagh
- Department of Micro and Nanosystems, KTH - Royal Institute of Technology , 10044 Stockholm, Sweden
| | - Wouter van der Wijngaart
- Department of Micro and Nanosystems, KTH - Royal Institute of Technology , 10044 Stockholm, Sweden
| | - Tommy Haraldsson
- Department of Micro and Nanosystems, KTH - Royal Institute of Technology , 10044 Stockholm, Sweden
| | - Jan Linnros
- Department of Applied Physics, KTH - Royal Institute of Technology , 16440 Stockholm, Sweden
| | - Jonathan G C Veinot
- Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2G2, Canada
| | - Sergei Popov
- Department of Applied Physics, KTH - Royal Institute of Technology , 16440 Stockholm, Sweden
| | - Ilya Sychugov
- Department of Applied Physics, KTH - Royal Institute of Technology , 16440 Stockholm, Sweden
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10
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Chistyakov AA, Zvaigzne MA, Nikitenko VR, Tameev AR, Martynov IL, Prezhdo OV. Optoelectronic Properties of Semiconductor Quantum Dot Solids for Photovoltaic Applications. J Phys Chem Lett 2017; 8:4129-4139. [PMID: 28799772 DOI: 10.1021/acs.jpclett.7b00671] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Quantum dot (QD) solids represent a new type of condensed matter drawing high fundamental and applied interest. Quantum confinement in individual QDs, combined with macroscopic scale whole materials, leads to novel exciton and charge transfer features that are particularly relevant to optoelectronic applications. This Perspective discusses the structure of semiconductor QD solids, optical and spectral properties, charge carrier transport, and photovoltaic applications. The distance between adjacent nanoparticles and surface ligands influences greatly electrostatic interactions between QDs and, hence, charge and energy transfer. It is almost inevitable that QD solids exhibit energetic disorder that bears many similarities to disordered organic semiconductors, with charge and exciton transport described by the multiple trapping model. QD solids are synthesized at low cost from colloidal solutions by casting, spraying, and printing. A judicious selection of a layer sequence involving QDs with different size, composition, and ligands can be used to harvest sunlight over a wide spectral range, leading to inexpensive and efficient photovoltaic devices.
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Affiliation(s)
- A A Chistyakov
- National Research Nuclear University "MEPhI" (Moscow Engineering Physics Institute) , Moscow 115409, Russia
| | - M A Zvaigzne
- National Research Nuclear University "MEPhI" (Moscow Engineering Physics Institute) , Moscow 115409, Russia
| | - V R Nikitenko
- National Research Nuclear University "MEPhI" (Moscow Engineering Physics Institute) , Moscow 115409, Russia
| | - A R Tameev
- National Research Nuclear University "MEPhI" (Moscow Engineering Physics Institute) , Moscow 115409, Russia
- A.N. Frumkin Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences , 31-building 4 Leninsky Prospect, Moscow 119071, Russia
| | - I L Martynov
- National Research Nuclear University "MEPhI" (Moscow Engineering Physics Institute) , Moscow 115409, Russia
| | - O V Prezhdo
- National Research Nuclear University "MEPhI" (Moscow Engineering Physics Institute) , Moscow 115409, Russia
- Department of Chemistry, Department of Physics, and Department of Astronomy, University of Southern California , Los Angeles, California 90089, United States
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11
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Labrador-Páez L, Jovanović DJ, Marqués MI, Smits K, Dolić SD, Jaque F, Stanley HE, Dramićanin MD, García-Solé J, Haro-González P, Jaque D. Unveiling Molecular Changes in Water by Small Luminescent Nanoparticles. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2017; 13:1700968. [PMID: 28605131 DOI: 10.1002/smll.201700968] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 04/21/2017] [Indexed: 06/07/2023]
Abstract
Nowadays a large variety of applications are based on solid nanoparticles dispersed in liquids-so called nanofluids. The interaction between the fluid and the nanoparticles plays a decisive role in the physical properties of the nanofluid. A novel approach based on the nonradiative energy transfer between two small luminescent nanocrystals (GdVO4 :Nd3+ and GdVO4 :Yb3+ ) dispersed in water is used in this work to investigate how temperature affects both the processes of interaction between nanoparticles and the effect of the fluid on the nanoparticles. From a systematic analysis of the effect of temperature on the GdVO4 :Nd3+ → GdVO4 :Yb3+ interparticle energy transfer, it can be concluded that a dramatic increase in the energy transfer efficiency occurs for temperatures above 45 °C. This change is properly explained by taking into account a crossover existing in diverse water properties that occurs at about this temperature. The obtained results allow elucidation on the molecular arrangement of water molecules below and above this crossover temperature. In addition, it is observed that an energy transfer process is produced as a result of interparticle collisions that induce irreversible ion exchange between the interacting nanoparticles.
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Affiliation(s)
- Lucía Labrador-Páez
- Fluorescence Imaging Group, Departamento de Física de Materiales, Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - Dragana J Jovanović
- Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, 11001, Serbia
| | - Manuel I Marqués
- Departamento de Física de Materiales, Universidad Autónoma de Madrid, Madrid, 28049, Spain
- Condensed Matter Physics Center (IFIMAC) and Nicolás Cabrera Institute, Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - Krisjanis Smits
- Institute of Solid State Physics, University of Latvia, Riga, LV-1063, Latvia
| | - Slobodan D Dolić
- Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, 11001, Serbia
| | - Francisco Jaque
- Condensed Matter Physics Center (IFIMAC) and Nicolás Cabrera Institute, Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - Harry Eugene Stanley
- Center for Polymer Studies and Department of Physics, Boston University, MA, 02215, USA
| | - Miroslav D Dramićanin
- Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, 11001, Serbia
| | - José García-Solé
- Fluorescence Imaging Group, Departamento de Física de Materiales, Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - Patricia Haro-González
- Fluorescence Imaging Group, Departamento de Física de Materiales, Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - Daniel Jaque
- Fluorescence Imaging Group, Departamento de Física de Materiales, Universidad Autónoma de Madrid, Madrid, 28049, Spain
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12
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Shavel A, Guerrini L, Alvarez-Puebla RA. Colloidal synthesis of silicon nanoparticles in molten salts. NANOSCALE 2017; 9:8157-8163. [PMID: 28581015 DOI: 10.1039/c7nr01839h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Silicon nanoparticles are unique materials with applications in a variety of fields, from electronics to catalysis and biomedical uses. Despite technological advancements in nanofabrication, the development of a simple and inexpensive route for the synthesis of homogeneous silicon nanoparticles remains highly challenging. Herein, we describe a new, simple and inexpensive colloidal synthetic method for the preparation, under normal pressure and mild temperature conditions, of relatively homogeneous spherical silicon nanoparticles of either ca. 4 or 6 nm diameter. The key features of this method are the selection of a eutectic salt mixture as a solvent, the identification of appropriate silicon alkoxide precursors, and the unconventional use of alkali earth metals as shape-controlling agents.
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Affiliation(s)
- A Shavel
- Medcom Advance SA, Viladecans Business Park - Edificio Brasil, Bertran i Musitu 83-85 08840, Viladecans (Barcelona), Spain.
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13
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Dandu N, Tretiak S, Kilina S, Kilin D. Through space and through bridge channels of charge transfer at p-n nano-junctions: A DFT study. Chem Phys 2016. [DOI: 10.1016/j.chemphys.2016.09.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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14
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Su Y, Ji X, He Y. Water-Dispersible Fluorescent Silicon Nanoparticles and their Optical Applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2016; 28:10567-10574. [PMID: 27529602 DOI: 10.1002/adma.201601173] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 06/15/2016] [Indexed: 05/07/2023]
Abstract
Fluorescent silicon nanoparticles (SiNPs) attract considerable attention owing to their intrinsic advantages, including relatively strong fluorescence coupled with robust photostability, rich resource support and relatively low cost, industrial maturity, and good biocompatibility. Extensive efforts are devoted to developing effective methods for the synthesis of hydrogen or halogen-terminated SiNPs, which nevertheless need further surface modification to improve their stability and solubility for wide-ranging applications. Notably, recent years have witnessed the development of various aqueous synthetic strategies for direct preparation of highly fluorescent and photostable SiNPs in the aqueous phase, facilitating the promotion of this promising material for myriad optical applications. Here, a concise discussion of the latest exciting research progress of the preparation of SiNPs is given, with a focus on water-dispersible SiNPs synthesized in the aqueous phase. In addition, representative optical applications of SiNPs in bioimaging and sensing are also summarized. Finally, the opportunities and challenges of fluorescent-SiNP-based optical applications are discussed.
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Affiliation(s)
- Yuanyuan Su
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China
| | - Xiaoyuan Ji
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China
| | - Yao He
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, P. R. China
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15
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Kilina SV, Tamukong PK, Kilin DS. Surface Chemistry of Semiconducting Quantum Dots: Theoretical Perspectives. Acc Chem Res 2016; 49:2127-2135. [PMID: 27669357 DOI: 10.1021/acs.accounts.6b00196] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Colloidal quantum dots (QDs) are near-ideal nanomaterials for energy conversion and lighting technologies. However, their photophysics exhibits supreme sensitivity to surface passivation and defects, of which control is problematic. The role of passivating ligands in photodynamics remains questionable and is a focus of ongoing research. The optically forbidden nature of surface-associated states makes direct measurements on them challenging. Therefore, computational modeling is imperative for insights into surface passivation and its impact on light-driven processes in QDs. This Account discusses challenges and recent progress in understanding surface effects on the photophysics of QDs addressed via quantum-chemical calculations. We overview different methods, including the effective mass approximation (EMA), time-dependent density functional theory (TDDFT), and multiconfiguration approaches, considering their strengths and weaknesses relevant to modeling of QDs with a complicated surface. We focus on CdSe, PbSe, and Si QDs, where calculations successfully explain experimental trends sensitive to surface defects, doping, and ligands. We show that the EMA accurately describes both linear and nonlinear optical properties of large-sized CdSe QDs (>2.5 nm), while TDDFT is required for smaller QDs where surface effects dominate. Both approaches confirm efficient two-photon absorption enabling applications of QDs as nonlinear optical materials. TDDFT also describes the effects of morphology on the optical response of QDs: the photophysics of stoichiometric, magic-sized XnYn (X = Cd, Pb; Y = S, Se) QDs is less sensitive to their passivation compared with nonstoichiometric Xn≠mYm QDs. In the latter, surface-driven optically inactive midgap states can be eliminated by anionic ligands, explaining the better emission of metal-enriched QDs compared with nonmetal-enriched QDs. Ideal passivation of magic-sized QDs by amines and phosphine oxides leaves lower-energy transitions intact, while thiol derivatives add ligand-localized trap states to the band gap. Depending on its position, any loss of ligand from the QD's surface also introduces electron or hole traps, decreasing the QD's luminescence. TDDFT investigations of QD-ligand and QD-QD interactions provide an explanation of experimentally detected enhancement of blinking on-times in closely packed Si QDs and establish favorable conditions for hole transfer from the photoexcited CdSe QD to metal-organic dyes. While TDDFT well describes qualitative trends in optical response to stoichiometry and ligand modifications of QDs, it is unable to calculate highly correlated electronic states like biexcitons and magnetic-dopant-derived states. In these cases, multiconfiguration methods are applied to small nanoclusters and the results are extrapolated to larger-sized QDs, providing reasonable explanations of experimental observables. For light-driven dynamics, the electron-phonon couplings are important, and nonadiabatic dynamics (NAD) is applied. NAD based on first-principles calculations is a current grand challenge for the theory. However, it can be accomplished through sets of semiclassical approximations such as surface hopping (SH). We discuss validations of approximations used in photodynamics of ligated and doped QDs. Time-domain DFT-based SH-NAD reveals the ligand's role in ultrafast energy relaxation and the connection between the phonon bottleneck and the Zeno effect in CdSe QDs. The calculated results are helpful in controlling both dissipation and radiative processes in QDs via surface engineering and in explanations of experimental data.
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Affiliation(s)
- Svetlana V. Kilina
- Department of Chemistry
and Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Patrick K. Tamukong
- Department of Chemistry
and Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Dmitri S. Kilin
- Department of Chemistry
and Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
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16
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Elbaradei A, Brown SL, Miller JB, May S, Hobbie EK. Interaction of polymer-coated silicon nanocrystals with lipid bilayers and surfactant interfaces. Phys Rev E 2016; 94:042804. [PMID: 27841530 DOI: 10.1103/physreve.94.042804] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Indexed: 06/06/2023]
Abstract
We use photoluminescence (PL) microscopy to measure the interaction between polyethylene-glycol-coated (PEGylated) silicon nanocrystals (SiNCs) and two model surfaces: lipid bilayers and surfactant interfaces. By characterizing the photostability, transport, and size-dependent emission of the PEGylated nanocrystal clusters, we demonstrate the retention of red PL suitable for detection and tracking with minimal blueshift after a year in an aqueous environment. The predominant interaction measured for both interfaces is short-range repulsion, consistent with the ideal behavior anticipated for PEGylated phospholipid coatings. However, we also observe unanticipated attractive behavior in a small number of scenarios for both interfaces. We attribute this anomaly to defective PEG coverage on a subset of the clusters, suggesting a possible strategy for enhancing cellular uptake by controlling the homogeneity of the PEG corona. In both scenarios, the shape of the apparent potential is modeled through the free or bound diffusion of the clusters near the confining interface.
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Affiliation(s)
- Ahmed Elbaradei
- North Dakota State University, Fargo, North Dakota 58108, USA
| | - Samuel L Brown
- North Dakota State University, Fargo, North Dakota 58108, USA
| | - Joseph B Miller
- North Dakota State University, Fargo, North Dakota 58108, USA
| | - Sylvio May
- North Dakota State University, Fargo, North Dakota 58108, USA
| | - Erik K Hobbie
- North Dakota State University, Fargo, North Dakota 58108, USA
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17
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Kortshagen UR, Sankaran RM, Pereira RN, Girshick SL, Wu JJ, Aydil ES. Nonthermal Plasma Synthesis of Nanocrystals: Fundamental Principles, Materials, and Applications. Chem Rev 2016; 116:11061-127. [DOI: 10.1021/acs.chemrev.6b00039] [Citation(s) in RCA: 248] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Uwe R. Kortshagen
- Department
of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - R. Mohan Sankaran
- Department
of Chemical Engineering, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Rui N. Pereira
- Department
of Physics and I3N, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
- Walter
Schottky Institut and Physik-Department, Technische Universität München, Am Coulombwall 4, 85748 Garching, Germany
| | - Steven L. Girshick
- Department
of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Jeslin J. Wu
- Department
of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Eray S. Aydil
- Department
of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
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18
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Gan Z, Lin Y, Luo L, Han G, Liu W, Liu Z, Yao C, Weng L, Liao L, Chen J, Liu X, Luo Y, Wang C, Wei S, Wu Z. Fluorescent Gold Nanoclusters with Interlocked Staples and a Fully Thiolate-Bound Kernel. Angew Chem Int Ed Engl 2016; 55:11567-71. [DOI: 10.1002/anie.201606661] [Citation(s) in RCA: 130] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Indexed: 12/16/2022]
Affiliation(s)
- Zibao Gan
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures; Institute of Solid State Physics; Chinese Academy of Sciences; Hefei 230031 China
| | - Yuejian Lin
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry; Fudan University; Shanghai 200433 China
| | - Lun Luo
- State Key Laboratory of Fine Chemicals; School of Pharmaceutical Science and Technology; Dalian University of Technology; Dalian 116024 China
| | - Guangmei Han
- Institute of Intelligent Machines; Chinese Academy of Sciences; Hefei 230031 China
| | - Wei Liu
- National Synchrotron Radiation Facility; University of Science and Technology of China; Hefei 230029 China
| | - Zhengjie Liu
- Institute of Intelligent Machines; Chinese Academy of Sciences; Hefei 230031 China
| | - Chuanhao Yao
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures; Institute of Solid State Physics; Chinese Academy of Sciences; Hefei 230031 China
| | - Linhong Weng
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry; Fudan University; Shanghai 200433 China
| | - Lingwen Liao
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures; Institute of Solid State Physics; Chinese Academy of Sciences; Hefei 230031 China
| | - Jishi Chen
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures; Institute of Solid State Physics; Chinese Academy of Sciences; Hefei 230031 China
| | - Xu Liu
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures; Institute of Solid State Physics; Chinese Academy of Sciences; Hefei 230031 China
| | - Yi Luo
- State Key Laboratory of Fine Chemicals; School of Pharmaceutical Science and Technology; Dalian University of Technology; Dalian 116024 China
| | - Chengming Wang
- Hefei National Laboratory for Physical Sciences at the Microscale; University of Science and Technology of China; Hefei 230026 China
| | - Shiqiang Wei
- National Synchrotron Radiation Facility; University of Science and Technology of China; Hefei 230029 China
| | - Zhikun Wu
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures; Institute of Solid State Physics; Chinese Academy of Sciences; Hefei 230031 China
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19
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Gan Z, Lin Y, Luo L, Han G, Liu W, Liu Z, Yao C, Weng L, Liao L, Chen J, Liu X, Luo Y, Wang C, Wei S, Wu Z. Fluorescent Gold Nanoclusters with Interlocked Staples and a Fully Thiolate-Bound Kernel. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201606661] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Zibao Gan
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures; Institute of Solid State Physics; Chinese Academy of Sciences; Hefei 230031 China
| | - Yuejian Lin
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry; Fudan University; Shanghai 200433 China
| | - Lun Luo
- State Key Laboratory of Fine Chemicals; School of Pharmaceutical Science and Technology; Dalian University of Technology; Dalian 116024 China
| | - Guangmei Han
- Institute of Intelligent Machines; Chinese Academy of Sciences; Hefei 230031 China
| | - Wei Liu
- National Synchrotron Radiation Facility; University of Science and Technology of China; Hefei 230029 China
| | - Zhengjie Liu
- Institute of Intelligent Machines; Chinese Academy of Sciences; Hefei 230031 China
| | - Chuanhao Yao
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures; Institute of Solid State Physics; Chinese Academy of Sciences; Hefei 230031 China
| | - Linhong Weng
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry; Fudan University; Shanghai 200433 China
| | - Lingwen Liao
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures; Institute of Solid State Physics; Chinese Academy of Sciences; Hefei 230031 China
| | - Jishi Chen
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures; Institute of Solid State Physics; Chinese Academy of Sciences; Hefei 230031 China
| | - Xu Liu
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures; Institute of Solid State Physics; Chinese Academy of Sciences; Hefei 230031 China
| | - Yi Luo
- State Key Laboratory of Fine Chemicals; School of Pharmaceutical Science and Technology; Dalian University of Technology; Dalian 116024 China
| | - Chengming Wang
- Hefei National Laboratory for Physical Sciences at the Microscale; University of Science and Technology of China; Hefei 230026 China
| | - Shiqiang Wei
- National Synchrotron Radiation Facility; University of Science and Technology of China; Hefei 230029 China
| | - Zhikun Wu
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures; Institute of Solid State Physics; Chinese Academy of Sciences; Hefei 230031 China
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20
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Chang IY, Kim D, Hyeon-Deuk K. Control of Electronic Structures and Phonon Dynamics in Quantum Dot Superlattices by Manipulation of Interior Nanospace. ACS APPLIED MATERIALS & INTERFACES 2016; 8:18321-18327. [PMID: 27385641 DOI: 10.1021/acsami.6b03219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Quantum dot (QD) superlattices, periodically ordered array structures of QDs, are expected to provide novel photo-optical functions due to their resonant couplings between adjacent QDs. Here, we computationally demonstrated that electronic structures and phonon dynamics of a QD superlattice can be effectively and selectively controlled by manipulating its interior nanospace, where quantum resonance between neighboring QDs appears, rather than by changing component QD size, shape, compositions, etc. A simple H-passivated Si QD was examined to constitute one-, two-, and three-dimensional QD superlattices, and thermally fluctuating band energies and phonon modes were simulated by finite-temperature ab initio molecular dynamics (MD) simulations. The QD superlattice exhibited a decrease in the band gap energy enhanced by thermal modulations and also exhibited selective extraction of charge carriers out of the component QD, indicating its advantage as a promising platform for implementation in solar cells. Our dynamical phonon analyses based on the ab initio MD simulations revealed that THz-frequency phonon modes were created by an inter-QD crystalline lattice formed in the QD superlattice, which can contribute to low energy thermoelectric conversion and will be useful for direct observation of the dimension-dependent superlattice. Further, we found that crystalline and ligand-originated phonon modes inside each component QD can be independently controlled by asymmetry of the superlattice and by restriction of the interior nanospace, respectively. Taking into account the thermal effects at the finite temperature, we proposed guiding principles for designing efficient and space-saving QD superlattices to develop functional photovoltaic and thermoelectric devices.
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Affiliation(s)
- I-Ya Chang
- Department of Chemistry, Kyoto University , Kyoto 606-8502, Japan
- PRESTO, Japan Science and Technology Agency , 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - DaeGwi Kim
- Department of Applied Physics, Osaka City University , Osaka 558-8585, Japan
| | - Kim Hyeon-Deuk
- Department of Chemistry, Kyoto University , Kyoto 606-8502, Japan
- PRESTO, Japan Science and Technology Agency , 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
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21
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Kislitsyn DA, Mills JM, Kocevski V, Chiu SK, DeBenedetti WJI, Gervasi CF, Taber BN, Rosenfield AE, Eriksson O, Rusz J, Goforth AM, Nazin GV. Communication: Visualization and spectroscopy of defects induced by dehydrogenation in individual silicon nanocrystals. J Chem Phys 2016; 144:241102. [DOI: 10.1063/1.4954833] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Dmitry A. Kislitsyn
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, 1253 University of Oregon, Eugene, Oregon 97403, USA
| | - Jon M. Mills
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, 1253 University of Oregon, Eugene, Oregon 97403, USA
| | - Vancho Kocevski
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, SE-751 20 Uppsala, Sweden
| | - Sheng-Kuei Chiu
- Department of Chemistry, Portland State University, Portland, Oregon 97201, USA
| | | | - Christian F. Gervasi
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, 1253 University of Oregon, Eugene, Oregon 97403, USA
| | - Benjamen N. Taber
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, 1253 University of Oregon, Eugene, Oregon 97403, USA
| | - Ariel E. Rosenfield
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, 1253 University of Oregon, Eugene, Oregon 97403, USA
| | - Olle Eriksson
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, SE-751 20 Uppsala, Sweden
| | - Ján Rusz
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, SE-751 20 Uppsala, Sweden
| | - Andrea M. Goforth
- Department of Chemistry, Portland State University, Portland, Oregon 97201, USA
| | - George V. Nazin
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, 1253 University of Oregon, Eugene, Oregon 97403, USA
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22
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Pelzer KM, Darling SB, Gray SK, Schaller RD. Exciton size and quantum transport in nanoplatelets. J Chem Phys 2016; 143:224106. [PMID: 26671357 DOI: 10.1063/1.4936407] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Two-dimensional nanoplatelets (NPLs) are an exciting class of materials with promising optical and energy transport properties. The possibility of efficient energy transport between nanoplatelets raises questions regarding the nature of energy transfer in these thin, laterally extended systems. A challenge in understanding exciton transport is the uncertainty regarding the size of the exciton. Depending on the material and defects in the nanoplatelet, an exciton could plausibly extend over an entire plate or localize to a small region. The variation in possible exciton sizes raises the question how exciton size impacts the efficiency of transport between nanoplatelet structures. Here, we explore this issue using a quantum master equation approach. This method goes beyond the assumptions of Förster theory to allow for quantum mechanical effects that could increase energy transfer efficiency. The model is extremely flexible in describing different systems, allowing us to test the effect of varying the spatial extent of the exciton. We first discuss qualitative aspects of the relationship between exciton size and transport and then conduct simulations of exciton transport between NPLs for a range of exciton sizes and environmental conditions. Our results reveal that exciton size has a strong effect on energy transfer efficiency and suggest that manipulation of exciton size may be useful in designing NPLs for energy transport.
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Affiliation(s)
- Kenley M Pelzer
- Center for Nanoscale Materials, Argonne National Laboratory, 9700 Cass Ave., Argonne, Illinois 60439, USA
| | - Seth B Darling
- Center for Nanoscale Materials, Argonne National Laboratory, 9700 Cass Ave., Argonne, Illinois 60439, USA
| | - Stephen K Gray
- Center for Nanoscale Materials, Argonne National Laboratory, 9700 Cass Ave., Argonne, Illinois 60439, USA
| | - Richard D Schaller
- Center for Nanoscale Materials, Argonne National Laboratory, 9700 Cass Ave., Argonne, Illinois 60439, USA
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23
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Kislitsyn DA, Kocevski V, Mills JM, Chiu SK, Gervasi CF, Taber BN, Rosenfield AE, Eriksson O, Rusz J, Goforth AM, Nazin GV. Mapping of Defects in Individual Silicon Nanocrystals Using Real-Space Spectroscopy. J Phys Chem Lett 2016; 7:1047-1054. [PMID: 26938674 DOI: 10.1021/acs.jpclett.6b00176] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The photophysical properties of silicon semiconductor nanocrystals (SiNCs) are extremely sensitive to the presence of surface chemical defects, many of which are easily produced by oxidation under ambient conditions. The diversity of chemical structures of such defects and the lack of tools capable of probing individual defects continue to impede understanding of the roles of these defects in SiNC photophysics. We use scanning tunneling spectroscopy to study the impact of surface defects on the electronic structures of hydrogen-passivated SiNCs supported on the Au(111) surface. Spatial maps of the local electronic density of states (LDOS) produced by our measurements allowed us to identify locally enhanced defect-induced states as well as quantum-confined states delocalized throughout the SiNC volume. We use theoretical calculations to show that the LDOS spectra associated with the observed defects are attributable to Si-O-Si bridged oxygen or Si-OH surface defects.
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Affiliation(s)
- Dmitry A Kislitsyn
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon , 1253 University of Oregon, Eugene, Oregon 97403, United States
| | - Vancho Kocevski
- Department of Physics and Astronomy, Uppsala University , Box 516, SE-751 20 Uppsala, Sweden
| | - Jon M Mills
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon , 1253 University of Oregon, Eugene, Oregon 97403, United States
| | - Sheng-Kuei Chiu
- Department of Chemistry, Portland State University , Portland, Oregon 97201, United States
| | - Christian F Gervasi
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon , 1253 University of Oregon, Eugene, Oregon 97403, United States
| | - Benjamen N Taber
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon , 1253 University of Oregon, Eugene, Oregon 97403, United States
| | - Ariel E Rosenfield
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon , 1253 University of Oregon, Eugene, Oregon 97403, United States
| | - Olle Eriksson
- Department of Physics and Astronomy, Uppsala University , Box 516, SE-751 20 Uppsala, Sweden
| | - Ján Rusz
- Department of Physics and Astronomy, Uppsala University , Box 516, SE-751 20 Uppsala, Sweden
| | - Andrea M Goforth
- Department of Chemistry, Portland State University , Portland, Oregon 97201, United States
| | - George V Nazin
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon , 1253 University of Oregon, Eugene, Oregon 97403, United States
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Tamukong PK, Peiris WDN, Kilina S. Computational insights into CdSe quantum dots' interactions with acetate ligands. Phys Chem Chem Phys 2016; 18:20499-510. [DOI: 10.1039/c6cp01665k] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Using density functional theory (DFT) and time-dependent DFT (TDDFT), we investigate the effects of carboxylate groups on the electronic and optical properties of CdSe quantum dots (QDs).
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Affiliation(s)
- Patrick K. Tamukong
- Department of Chemistry and Biochemistry
- North Dakota State University
- Fargo
- USA
| | | | - Svetlana Kilina
- Department of Chemistry and Biochemistry
- North Dakota State University
- Fargo
- USA
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