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Duan J, Wang J, Hou L, Ji P, Zhang W, Liu J, Zhu X, Sun Z, Ma Y, Ma L. Application of Scanning Tunneling Microscopy and Spectroscopy in the Studies of Colloidal Quantum Qots. CHEM REC 2023; 23:e202300120. [PMID: 37255365 DOI: 10.1002/tcr.202300120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/15/2023] [Indexed: 06/01/2023]
Abstract
Colloidal quantum dots display remarkable optical and electrical characteristics with the potential for extensive applications in contemporary nanotechnology. As an ideal instrument for examining surface topography and local density of states (LDOS) at an atomic scale, scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) has become indispensable approaches to gain better understanding of their physical properties. This article presents a comprehensive review of the research advancements in measuring the electronic orbits and corresponding energy levels of colloidal quantum dots in various systems using STM and STS. The first three sections introduce the basic principles of colloidal quantum dots synthesis and the fundamental methodology of STM research on quantum dots. The fourth section explores the latest progress in the application of STM for colloidal quantum dot studies. Finally, a summary and prospective is presented.
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Affiliation(s)
- Jiaying Duan
- Tianjin International Center for Nanoparticles and NanoSystems, Tianjin University, Tianjin, China, 300072
| | - Jiapeng Wang
- Tianjin International Center for Nanoparticles and NanoSystems, Tianjin University, Tianjin, China, 300072
| | - Liangpeng Hou
- Tianjin International Center for Nanoparticles and NanoSystems, Tianjin University, Tianjin, China, 300072
| | - Peixuan Ji
- Tianjin International Center for Nanoparticles and NanoSystems, Tianjin University, Tianjin, China, 300072
| | - Wusheng Zhang
- Tianjin International Center for Nanoparticles and NanoSystems, Tianjin University, Tianjin, China, 300072
| | - Jin Liu
- Tianjin International Center for Nanoparticles and NanoSystems, Tianjin University, Tianjin, China, 300072
| | - Xiaodong Zhu
- Tianjin International Center for Nanoparticles and NanoSystems, Tianjin University, Tianjin, China, 300072
| | - Zhixiang Sun
- Center for Joint Quantum Studies and Department of Physics, School of Science, Tianjin University, Tianjin, China, 300072
| | - Yanqing Ma
- Tianjin International Center for Nanoparticles and NanoSystems, Tianjin University, Tianjin, China, 300072
| | - Lei Ma
- Tianjin International Center for Nanoparticles and NanoSystems, Tianjin University, Tianjin, China, 300072
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2
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Parra GG, Pavanelli AL, Franco LP, Máximo LN, da Silva RS, Borissevitch I. Interaction of CdTe-MPA quantum dots with meso-tetra methyl pyridyl porphyrin. Charge transfer complex formation. J Photochem Photobiol A Chem 2020. [DOI: 10.1016/j.jphotochem.2020.112580] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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3
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Hanna L, Lockard JV. From IR to x-rays: gaining molecular level insights on metal-organic frameworks through spectroscopy. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:483001. [PMID: 31387089 DOI: 10.1088/1361-648x/ab38da] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This topical review focuses on the application of several types of spectroscopy methods to a class of solid state materials called metal organic frameworks (MOFs). MOFs are self-assembled, porous crystalline materials composed of metal cluster nodes linked through coordination bonds with organic or organometallic molecular constituents. Their unique host-guest properties make them attractive for many adsorption-based applications such as gas storage and separation, catalysis, sensing and others. While much research focuses on the development and application of these materials, fundamental studies of MOF properties and molecular level host-guest interactions behind their functionality have become a significant research direction on its own. Spectroscopy methods are now ubiquitous tools in this pursuit. This review focuses on the application of three classes of spectroscopy methods to MOF materials: vibrational, optical electronic and x-ray spectroscopies. Following brief introductions to each method that include pertinent theory and experimental considerations, we present a broad overview of the types of MOF systems that have been studied, with specific examples and important new molecular level insights highlighted along the way. The current status of spectroscopic studies of MOFs is presented at the end along with some perspectives on the future directions in this area of research.
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Affiliation(s)
- Lauren Hanna
- Department of Chemistry, Rutgers University, Newark, NJ 07102, United States of America
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4
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Chuang CH, Porel M, Choudhury R, Burda C, Ramamurthy V. Ultrafast Electron Transfer across a Nanocapsular Wall: Coumarins as Donors, Viologen as Acceptor, and Octa Acid Capsule as the Mediator. J Phys Chem B 2017; 122:328-337. [DOI: 10.1021/acs.jpcb.7b11306] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Chi-Hung Chuang
- Center
for Chemical Dynamics and Nanomaterials Research, Department of Chemistry, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | - Mintu Porel
- Department
of Chemistry, University of Miami, Coral Gables, Florida 33124, United States
| | - Rajib Choudhury
- Department
of Physical Sciences, Arkansas Tech University, Russellville, Arkansas 72801, United States
| | - Clemens Burda
- Center
for Chemical Dynamics and Nanomaterials Research, Department of Chemistry, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | - V. Ramamurthy
- Department
of Chemistry, University of Miami, Coral Gables, Florida 33124, United States
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5
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Xu R, Liao C, Xu Y, Zhang C, Xiao M, Zhang L, Lu C, Cui Y, Zhang J. Bright type-II photoluminescence from Mn-doped CdS/ZnSe/ZnS quantum dots with Mn 2+ ions as exciton couplers. NANOSCALE 2017; 9:18281-18289. [PMID: 29139512 DOI: 10.1039/c7nr05670b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Mn2+ ions were introduced as exciton couplers to enhance the quantum yield (QY) of type-II photoluminescence (PL) from CdS/ZnSe/ZnS quantum dots (QDs) with slow hot-exciton cooling and low radiative rate. Transient absorption spectroscopy verifies the faster bleach recovery and faster peak red-shifting at the charge-transfer state. And the transient PL peak of the QDs changes from blue-shifting to red-shifting due to Mn2+ doping. The QY of type-II PL can be enhanced from ∼35% to ∼60% by Mn2+ doping. As the energy-transfer-stations of hot excitons during rapid ET (∼100 ps), Mn2+ ions transform more excitons from hot to cold for emission. As the couplers of cold excitons during long thermal equilibrium (∼100 ns), Mn2+ ions further decrease exciton trapping by strong bidirectional coupling. This work provides a unique way of acquiring high QY of type-II PL, and highlights the general law of PL enhancement in Mn-doped QDs.
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Affiliation(s)
- Ruilin Xu
- Advanced Photonic Center, Southeast University, Nanjing 210096, China.
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6
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Affiliation(s)
- Simanta Kundu
- Department
of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
| | - Amitava Patra
- Department
of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
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7
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Bose R, Bera A, Parida MR, Adhikari A, Shaheen BS, Alarousu E, Sun J, Wu T, Bakr OM, Mohammed OF. Real-Space Mapping of Surface Trap States in CIGSe Nanocrystals Using 4D Electron Microscopy. NANO LETTERS 2016; 16:4417-4423. [PMID: 27228321 DOI: 10.1021/acs.nanolett.6b01553] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Surface trap states in copper indium gallium selenide semiconductor nanocrystals (NCs), which serve as undesirable channels for nonradiative carrier recombination, remain a great challenge impeding the development of solar and optoelectronics devices based on these NCs. In order to design efficient passivation techniques to minimize these trap states, a precise knowledge about the charge carrier dynamics on the NCs surface is essential. However, selective mapping of surface traps requires capabilities beyond the reach of conventional laser spectroscopy and static electron microscopy; it can only be accessed by using a one-of-a-kind, second-generation four-dimensional scanning ultrafast electron microscope (4D S-UEM) with subpicosecond temporal and nanometer spatial resolutions. Here, we precisely map the collective surface charge carrier dynamics of copper indium gallium selenide NCs as a function of the surface trap states before and after surface passivation in real space and time using S-UEM. The time-resolved snapshots clearly demonstrate that the density of the trap states is significantly reduced after zinc sulfide (ZnS) shelling. Furthermore, the removal of trap states and elongation of carrier lifetime are confirmed by the increased photocurrent of the self-biased photodetector fabricated using the shelled NCs.
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Affiliation(s)
- Riya Bose
- Solar and Photovoltaics Engineering Research Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Ashok Bera
- Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Manas R Parida
- Solar and Photovoltaics Engineering Research Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Aniruddha Adhikari
- Solar and Photovoltaics Engineering Research Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Basamat S Shaheen
- Solar and Photovoltaics Engineering Research Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Erkki Alarousu
- Solar and Photovoltaics Engineering Research Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Jingya Sun
- Solar and Photovoltaics Engineering Research Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Tom Wu
- Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Osman M Bakr
- Solar and Photovoltaics Engineering Research Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Omar F Mohammed
- Solar and Photovoltaics Engineering Research Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900, Kingdom of Saudi Arabia
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8
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Lu J, Liu H, Tok ES, Sow CH. Interactions between lasers and two-dimensional transition metal dichalcogenides. Chem Soc Rev 2016; 45:2494-515. [DOI: 10.1039/c5cs00553a] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We review the interactions between lasers and TMDs with a focus on the use of laser-based technologies as effective tools for the characterization, modification, and manipulation of TMDs.
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Affiliation(s)
- Junpeng Lu
- Department of Physics
- National University of Singapore
- Singapore 117542
- Singapore
- Center for Advanced 2D materials and Graphene Research Center
| | - Hongwei Liu
- Institute of Materials Research and Engineering
- A*STAR (Agency for Science, Technology and Research)
- Singapore 138634
- Singapore
| | - Eng Soon Tok
- Department of Physics
- National University of Singapore
- Singapore 117542
- Singapore
| | - Chorng-Haur Sow
- Department of Physics
- National University of Singapore
- Singapore 117542
- Singapore
- Center for Advanced 2D materials and Graphene Research Center
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9
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Quantum dot effects upon the interaction between porphyrins and phospholipids in cell membrane models. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2015; 45:219-27. [DOI: 10.1007/s00249-015-1088-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 10/09/2015] [Indexed: 01/07/2023]
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10
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Bose R, Wasey AHMA, Das GP, Pradhan N. Heteroepitaxial Junction in Au-ZnSe Nanostructure: Experiment versus First-Principle Simulation. J Phys Chem Lett 2014; 5:1892-1898. [PMID: 26273870 DOI: 10.1021/jz500777k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Composing together the experimental as well as the simulated results, we demonstrate here the atomic placements and the electronic structure at the epitaxial junction of a solution-processed heteronanostructure Au-ZnSe. Despite the large lattice mismatch (∼32%) between fcc Au and zinc-blende structured ZnSe, the heterostructures are formed via coincidence site epitaxy, which appears periodically because of the arrangements of their proper unit cell placements at the junction. This reduces the interface energy and drives the formation of such heteronanostructures. Details of the physical processes involved in the formation of these nanostructures have been discussed in this letter, and epitaxy at the heterojunction is strongly supported by HRTEM measurement and DFT calculation. This material has the possibility of plasmon-exciton coupling and therefore might be a futuristic material for utilizations in catalysis, nanoelectronics, and other related applications.
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Affiliation(s)
- Riya Bose
- †Department of Materials Science, ‡Centre for Advanced Materials, Indian Association for the Cultivation of Science, Kolkata 700032, India
| | - A H M Abdul Wasey
- †Department of Materials Science, ‡Centre for Advanced Materials, Indian Association for the Cultivation of Science, Kolkata 700032, India
| | - Gour P Das
- †Department of Materials Science, ‡Centre for Advanced Materials, Indian Association for the Cultivation of Science, Kolkata 700032, India
| | - Narayan Pradhan
- †Department of Materials Science, ‡Centre for Advanced Materials, Indian Association for the Cultivation of Science, Kolkata 700032, India
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11
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Li ZJ, Fan XB, Li XB, Li JX, Ye C, Wang JJ, Yu S, Li CB, Gao YJ, Meng QY, Tung CH, Wu LZ. Visible light catalysis-assisted assembly of Ni(h)-QD hollow nanospheres in situ via hydrogen bubbles. J Am Chem Soc 2014; 136:8261-8. [PMID: 24835886 DOI: 10.1021/ja5047236] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hollow spheres are one of the most promising micro-/nanostructures because of their unique performance in diverse applications. Templates, surfactants, and structure-directing agents are often used to control the sizes and morphologies of hollow spheres. In this Article, we describe a simple method based on visible light catalysis for preparing hollow nanospheres from CdE (E = Te, Se, and S) quantum dots (QDs) and nickel (Ni(2+)) salts in aqueous media. In contrast to the well-developed traditional approaches, the hollow nanospheres of QDs are formed in situ by the photogeneration of hydrogen (H2) gas bubbles at room temperature. Each component, that is, the QDs, metal ions, ascorbic acid (H2A), and visible light, is essential for the formation of hollow nanospheres. The quality of the hollow nanospheres depends on the pH, metal ions, and wavelength and intensity of visible light used. Of the various metal ions investigated, including Cu(+), Cu(2+), Fe(2+), Fe(3+), Ni(2+), Mn(2+), RuCl5(2-), Ag(+), and PtCl4(2-), Ni(2+) ions showed the best ability to generate H2 and hollow-structured nanospheres under visible light irradiation. The average diameter and shell thickness of the nanospheres ranged from 10 to 20 nm and from 3 to 6 nm, respectively, which are values rarely reported in the literature. Studies using high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), inductively coupled plasma-mass spectroscopy (ICP-AES), and steady-state and time-resolved spectroscopy revealed the chemical nature of the hollow nanospheres. Additionally, the hollow-structured nanospheres exhibit excellent photocatalytic activity and stability for the generation of H2 with a rate constant of 21 μmol h(-1) mg(-1) and a turnover number (TON) of 137,500 or 30,250 for CdTe QDs or nickel, respectively, under visible light irradiation for 42 h.
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Affiliation(s)
- Zhi-Jun Li
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry & University of Chinese Academy of Sciences, Chinese Academy of Sciences , Beijing 100190, People's Republic of China
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12
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Affiliation(s)
- Lixia Sang
- Key
Laboratory of Enhanced Heat Transfer and Energy Conservation, Ministry
of Education and Key Laboratory of Heat Transfer and Energy Conversion,
Beijing Municipality, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China
| | - Yixin Zhao
- School
of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Clemens Burda
- Center
for Chemical Dynamics and Nanomaterials Research, Department of Chemistry, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
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13
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Lee E, Benayad A, Shin T, Lee H, Ko DS, Kim TS, Son KS, Ryu M, Jeon S, Park GS. Nanocrystalline ZnON; high mobility and low band gap semiconductor material for high performance switch transistor and image sensor application. Sci Rep 2014; 4:4948. [PMID: 24824778 PMCID: PMC4018964 DOI: 10.1038/srep04948] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 04/22/2014] [Indexed: 11/17/2022] Open
Abstract
Interest in oxide semiconductors stems from benefits, primarily their ease of process, relatively high mobility (0.3–10 cm2/vs), and wide-bandgap. However, for practical future electronic devices, the channel mobility should be further increased over 50 cm2/vs and wide-bandgap is not suitable for photo/image sensor applications. The incorporation of nitrogen into ZnO semiconductor can be tailored to increase channel mobility, enhance the optical absorption for whole visible light and form uniform micro-structure, satisfying the desirable attributes essential for high performance transistor and visible light photo-sensors on large area platform. Here, we present electronic, optical and microstructural properties of ZnON, a composite of Zn3N2 and ZnO. Well-optimized ZnON material presents high mobility exceeding 100 cm2V−1s−1, the band-gap of 1.3 eV and nanocrystalline structure with multiphase. We found that mobility, microstructure, electronic structure, band-gap and trap properties of ZnON are varied with nitrogen concentration in ZnO. Accordingly, the performance of ZnON-based device can be adjustable to meet the requisite of both switch device and image-sensor potentials. These results demonstrate how device and material attributes of ZnON can be optimized for new device strategies in display technology and we expect the ZnON will be applicable to a wide range of imaging/display devices.
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Affiliation(s)
- Eunha Lee
- Analytical Science Group, Samsung Advanced Institute of Technology, Samsung Electronics Corporations, Yongin-Si, Gyeonggi-Do, 446-712, Korea
| | - Anass Benayad
- Analytical Science Group, Samsung Advanced Institute of Technology, Samsung Electronics Corporations, Yongin-Si, Gyeonggi-Do, 446-712, Korea
| | - Taeho Shin
- Analytical Science Group, Samsung Advanced Institute of Technology, Samsung Electronics Corporations, Yongin-Si, Gyeonggi-Do, 446-712, Korea
| | - HyungIk Lee
- Analytical Science Group, Samsung Advanced Institute of Technology, Samsung Electronics Corporations, Yongin-Si, Gyeonggi-Do, 446-712, Korea
| | - Dong-Su Ko
- Analytical Science Group, Samsung Advanced Institute of Technology, Samsung Electronics Corporations, Yongin-Si, Gyeonggi-Do, 446-712, Korea
| | - Tae Sang Kim
- Display Lab, Samsung Advanced Institute of Technology, Samsung Electronics Corporations, Yongin-Si, Gyeonggi-Do, 446-712, Korea
| | - Kyoung Seok Son
- Display Lab, Samsung Advanced Institute of Technology, Samsung Electronics Corporations, Yongin-Si, Gyeonggi-Do, 446-712, Korea
| | - Myungkwan Ryu
- Display Lab, Samsung Advanced Institute of Technology, Samsung Electronics Corporations, Yongin-Si, Gyeonggi-Do, 446-712, Korea
| | - Sanghun Jeon
- Department of Applied Physics, Korea University, Sejongro Sejong, 339-700, Korea
| | - Gyeong-Su Park
- Analytical Science Group, Samsung Advanced Institute of Technology, Samsung Electronics Corporations, Yongin-Si, Gyeonggi-Do, 446-712, Korea
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14
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Liu L, Liu Z, Liu A, Gu X, Ge C, Gao F, Dong L. Engineering the TiO2 -graphene interface to enhance photocatalytic H2 production. CHEMSUSCHEM 2014; 7:618-26. [PMID: 24323576 DOI: 10.1002/cssc.201300941] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Indexed: 05/26/2023]
Abstract
In this work, TiO2 -graphene nanocomposites are synthesized with tunable TiO2 crystal facets ({100}, {101}, and {001} facets) through an anion-assisted method. These three TiO2 -graphene nanocomposites have similar particle sizes and surface areas; the only difference between them is the crystal facet exposed in TiO2 nanocrystals. UV/Vis spectra show that band structures of TiO2 nanocrystals and TiO2 -graphene nanocomposites are dependent on the crystal facets. Time-resolved photoluminescence spectra suggest that the charge-transfer rate between {100} facets and graphene is approximately 1.4 times of that between {001} facets and graphene. Photoelectrochemical measurements also confirm that the charge-separation efficiency between TiO2 and graphene is greatly dependent on the crystal facets. X-ray photoelectron spectroscopy reveals that Ti-C bonds are formed between {100} facets and graphene, while {101} facets and {001} facets are connected with graphene mainly through Ti-O-C bonds. With Ti-C bonds between TiO2 and graphene, TiO2 -100-G shows the fastest charge-transfer rate, leading to higher activity in photocatalytic H2 production from methanol solution. TiO2 -101-G with more reductive electrons and medium interfacial charge-transfer rate also shows good H2 evolution rate. As a result of its disadvantageous electronic structure and interfacial connections, TiO2 -001-G shows the lowest H2 evolution rate. These results suggest that engineering the structures of the TiO2 -graphene interface can be an effective strategy to achieve excellent photocatalytic performances.
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Affiliation(s)
- Lichen Liu
- Key Laboratory of Mesoscopic Chemistry of Ministry of Education, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (PR China)
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15
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McBride JR, Pennycook TJ, Pennycook SJ, Rosenthal SJ. The possibility and implications of dynamic nanoparticle surfaces. ACS NANO 2013; 7:8358-8365. [PMID: 24124980 DOI: 10.1021/nn403478h] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Understanding the precise nature of a surface or interface is a key component toward optimizing the desired properties and function of a material. For semiconductor nanocrystals, the surface has been shown to modulate fluorescence efficiency, lifetime, and intermittency. The theoretical picture of a nanocrystal surface has included the existence of an undefined mixture of trap states that arise from incomplete passivation. However, our recent scanning transmission electron microscope movies and supporting theoretical evidence suggest that, under excitation, the surface is fluctuating, creating a dynamic population of surface and subsurface states. This possibility challenges our fundamental understanding of the surface and could have far-reaching ramifications for nanoparticle-based technologies. In this Perspective, we discuss the current theories behind the optical properties of nanocrystals in the context of fluxionality.
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Affiliation(s)
- James R McBride
- Department of Chemistry, ‡Department of Physics and Astronomy, §Department of Pharmacology, ⊥Department of Chemical and Biomolecular Engineering, and The Vanderbilt Institute of Nanoscale Science and Engineering, Vanderbilt University , Nashville, Tennessee 37235, United States
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16
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Porel M, Chuang CH, Burda C, Ramamurthy V. Ultrafast Photoinduced Electron Transfer between an Incarcerated Donor and a Free Acceptor in Aqueous Solution. J Am Chem Soc 2012; 134:14718-21. [DOI: 10.1021/ja3067594] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Mintu Porel
- Department of Chemistry, University of Miami, Coral Gables, Florida 33124, United
States
| | - Chi-Hung Chuang
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106,
United States
| | - Clemens Burda
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106,
United States
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