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Atabay M, Sardroodi JJ, Ebrahimzadeh AR, Avestan MS. Modeling the Interaction of Anticancer Protein Azurin with the Nanosheets for Medical Applications. ChemistrySelect 2022. [DOI: 10.1002/slct.202202633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Maryam Atabay
- Molecular Simulation Lab Azarbaijan Shahid Madani University Tabriz Iran
- Molecular Science and Engineering Research Group (MSERG) Azarbaijan Shahid Madani University Tabriz Iran
- Department of Chemistry Azarbaijan Shahid Madani University Tabriz Iran
| | - Jaber Jahanbin Sardroodi
- Molecular Simulation Lab Azarbaijan Shahid Madani University Tabriz Iran
- Molecular Science and Engineering Research Group (MSERG) Azarbaijan Shahid Madani University Tabriz Iran
- Department of Chemistry Azarbaijan Shahid Madani University Tabriz Iran
| | - Alireza Rastkar Ebrahimzadeh
- Molecular Simulation Lab Azarbaijan Shahid Madani University Tabriz Iran
- Molecular Science and Engineering Research Group (MSERG) Azarbaijan Shahid Madani University Tabriz Iran
- Department of Physics Azarbaijan Shahid Madani University Tabriz Iran
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2
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Xi J, Szlufarska I. Control of Surface Chemical Reactions through Solid Stiffness. PHYSICAL REVIEW LETTERS 2022; 129:106101. [PMID: 36112460 DOI: 10.1103/physrevlett.129.106101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 08/14/2022] [Accepted: 08/17/2022] [Indexed: 06/15/2023]
Abstract
Control of surface reactions is commonly achieved by modification of surface electronic structures. Here, we discover an alternative pathway for controlling surface reactions by tuning the mechanical stiffness of the underlying material. We find that in addition to the typically assumed surface electronic contribution right at the reactive site, the contribution from the deformation of the bulk region plays a vital role in controlling surface reactions. The underlying mechanism is an elastic relaxation of the solid, which depends on the material's stiffness and can be modified by tuning bulk stoichiometry. The effect of bulk stiffness on surface reactions has been demonstrated by considering hydrogen scission reaction and oxygen incorporation reaction during corrosion of amorphous SiC in water and air, respectively. Our results imply that tuning of bulk stiffness by modifying stoichiometry can provide an effective method for controlling surface reactions.
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Affiliation(s)
- Jianqi Xi
- Department of Materials Science and Engineering, University of Wisconsin, Madison, Wisconsin 53706, USA
| | - Izabela Szlufarska
- Department of Materials Science and Engineering, University of Wisconsin, Madison, Wisconsin 53706, USA
- Department of Engineering Physics, University of Wisconsin, Madison, Wisconsin 53706, USA
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3
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The first-principles study on Mo-doped monolayer ReS 2. J Mol Model 2022; 28:93. [PMID: 35305175 DOI: 10.1007/s00894-022-05080-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 03/06/2022] [Indexed: 10/18/2022]
Abstract
Based on the first-principles calculations, the electronic structure and optical properties of the Mo-doped monolayer rhenium disulfide (ReS2) model are calculated, and the system stability, bond length, charge difference density, band structure, photoabsorption coefficient, system stability, and reflectivity are analyzed. The calculation results show that doping changes the structural stability of the system, which gradually decreases with an increasing concentration of doping. The calculation of band structure and density of states indicated that the band gap value of the system decreases continuously to 0 with increasing doping concentration, while the average charge population of atoms at doping sites keeps increasing with the better electron-losing ability of atoms. Compared with the intrinsic monolayer ReS2, the peak of systemic reflectivity at different doping concentrations has corresponding degrees of redshift in a certain wavelength range, as demonstrated by the optical properties.
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4
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Fu X, Wang D. Effect of surface bond and quantum confinement effect on photoluminescence properties of SiC nanowires in different solvents. INORG NANO-MET CHEM 2021. [DOI: 10.1080/24701556.2020.1793358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Xin Fu
- College of Chemistry and Material, Weinan Normal University, Weinan, P.R. China
| | - Donghua Wang
- College of Chemistry and Material, Weinan Normal University, Weinan, P.R. China
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5
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Muthukumaran T, Philip J. A facile approach to synthesis of cobalt ferrite nanoparticles with a uniform ultrathin layer of silicon carbide for organic dye removal. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.114110] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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6
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Katre A, Carrete J, Dongre B, Madsen GKH, Mingo N. Exceptionally Strong Phonon Scattering by B Substitution in Cubic SiC. PHYSICAL REVIEW LETTERS 2017; 119:075902. [PMID: 28949692 DOI: 10.1103/physrevlett.119.075902] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Indexed: 06/07/2023]
Abstract
We use ab initio calculations to predict the thermal conductivity of cubic SiC with different types of defects. An excellent quantitative agreement with previous experimental measurements is found. The results unveil that B_{C} substitution has a much stronger effect than any of the other defect types in 3C-SiC, including vacancies. This finding contradicts the prediction of the classical mass-difference model of impurity scattering, according to which the effects of B_{C} and N_{C} would be similar and much smaller than that of the C vacancy. The strikingly different behavior of the B_{C} defect arises from a unique pattern of resonant phonon scattering caused by the broken structural symmetry around the B impurity.
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Affiliation(s)
- Ankita Katre
- LITEN, CEA-Grenoble, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France
| | - Jesús Carrete
- Institute of Materials Chemistry, TU Wien, A-1060 Vienna, Austria
| | - Bonny Dongre
- Institute of Materials Chemistry, TU Wien, A-1060 Vienna, Austria
| | - Georg K H Madsen
- Institute of Materials Chemistry, TU Wien, A-1060 Vienna, Austria
| | - Natalio Mingo
- LITEN, CEA-Grenoble, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France
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7
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Li H, Shang J, Zhu H, Yang Z, Ai Z, Zhang L. Oxygen Vacancy Structure Associated Photocatalytic Water Oxidation of BiOCl. ACS Catal 2016. [DOI: 10.1021/acscatal.6b02613] [Citation(s) in RCA: 278] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hao Li
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People’s Republic of China
| | - Jian Shang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People’s Republic of China
| | - Huijun Zhu
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People’s Republic of China
| | - Zhiping Yang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People’s Republic of China
| | - Zhihui Ai
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People’s Republic of China
| | - Lizhi Zhang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, People’s Republic of China
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8
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Ochedowski O, Osmani O, Schade M, Bussmann BK, Ban-d’Etat B, Lebius H, Schleberger M. Graphitic nanostripes in silicon carbide surfaces created by swift heavy ion irradiation. Nat Commun 2014; 5:3913. [PMID: 24905053 DOI: 10.1038/ncomms4913] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Accepted: 04/07/2014] [Indexed: 11/09/2022] Open
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9
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Tocci G, Michaelides A. Solvent-Induced Proton Hopping at a Water-Oxide Interface. J Phys Chem Lett 2014; 5:474-480. [PMID: 24920998 PMCID: PMC4047599 DOI: 10.1021/jz402646c] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 01/15/2014] [Indexed: 05/16/2023]
Abstract
Despite widespread interest, a detailed understanding of the dynamics of proton transfer at interfaces is lacking. Here, we use ab initio molecular dynamics to unravel the connection between interfacial water structure and proton transfer for the widely studied and experimentally well-characterized water-ZnO(101̅0) interface. We find that upon going from a single layer of adsorbed water to a liquid multilayer, changes in the structure are accompanied by a dramatic increase in the proton-transfer rate at the surface. We show how hydrogen bonding and rather specific hydrogen-bond fluctuations at the interface are responsible for the change in the structure and proton-transfer dynamics. The implications of this for the chemical reactivity and for the modeling of complex wet oxide interfaces in general are also discussed.
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10
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Sun M, Xiong S, Wu X, He C, Li T, Chu PK. Enhanced photocatalytic oxygen evolution by crystal cutting. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2013; 25:2035-2039. [PMID: 23334954 DOI: 10.1002/adma.201203864] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Revised: 12/03/2012] [Indexed: 06/01/2023]
Abstract
Uniformly cut In2O3 truncated octahedrons are fabricated on a large scale by a simple chemical vapor deposition (CVD) technique. This theoretical analysis predicts that the emergence of {100} facets on the In2O3 truncated octahedrons enhances oxygen evolution significantly in photocatalysis and experimental photoelectrochemical measurements are consistent.
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Affiliation(s)
- Min Sun
- National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing, P R China
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11
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Shen X, Pantelides ST. Atomic-Scale Mechanism of Efficient Hydrogen Evolution at SiC Nanocrystal Electrodes. J Phys Chem Lett 2013; 4:100-104. [PMID: 26291219 DOI: 10.1021/jz301799w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Efficient electrochemical hydrogen evolution at ultrathin 3C-SiC nanocrystal electrodes in acid solutions was recently reported, but the atomic-scale mechanism of the reaction was not identified. Here we report quantum mechanical calculations of pertinent reactions and show that the reaction happens at pre-existing hydrogenated surface Si-H sites through a mechanism that is related to the Volmer-Heyrovsky mechanism that occurs in metals. Here the Heyrovsky reaction occurs as the first step, where an electron from the substrate reacts with a hydronium adsorbed at a Si-H site, creating an H2 molecule and a Si dangling bond. The Volmer reaction follows and regenerates the Si-H. This ordering of reactions is supported by the fact that the hydrogen coverage on SiC electrodes does not depend on the applied voltage, in contrast to the cases of metal electrodes. Moreover, the Volmer reaction, which is a one-step process on metal surface, is a two-step process here. We then show that the rise of the conduction band due to quantum confinement accounts for the fact that only ultrasmall SiC nanocrystals are electrochemically active. We also show that the ability of a Si-H bond to bind a hydronium is essential for the hydrogen evolution to occur at high rate.
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Affiliation(s)
| | - Sokrates T Pantelides
- §Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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12
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13
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He C, Wu X, Shen J, Chu PK. High-efficiency electrochemical hydrogen evolution based on surface autocatalytic effect of ultrathin 3C-SiC nanocrystals. NANO LETTERS 2012; 12:1545-8. [PMID: 22385070 DOI: 10.1021/nl3006947] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Good understanding of the reaction mechanism in the electrochemical reduction of water to hydrogen is crucial to renewable energy technologies. Although previous studies have revealed that the surface properties of materials affect the catalytic reactivity, the effects of a catalytic surface on the hydrogen evolution reaction (HER) on the molecular level are still not well understood. Contrary to general belief, water molecules do not adsorb onto the surfaces of 3C-SiC nanocrystals (NCs), but rather spontaneously dissociate via a surface autocatalytic process forming a complex consisting of -H and -OH fragments. In this study, we show that ultrathin 3C-SiC NCs possess superior electrocatalytic activity in the HER. This arises from the large reduction in the activation barrier on the NC surface enabling efficient dissociation of H(2)O molecules. Furthermore, the ultrathin 3C-SiC NCs show enhanced HER activity in photoelectrochemical cells and are very promising to the water splitting based on the synergistic electrocatalytic and photoelectrochemical actions. This study provides a molecular-level understanding of the HER mechanism and reveals that NCs with surface autocatalytic effects can be used to split water with high efficiency thereby enabling renewable and economical production of hydrogen.
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Affiliation(s)
- Chengyu He
- National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China
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14
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Reactivity of H2O and the Si-terminated surface of silicon carbide studied with ONIOM method. Theor Chem Acc 2012. [DOI: 10.1007/s00214-012-1101-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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15
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Diverse Role of Silicon Carbide in the Domain of Nanomaterials. INTERNATIONAL JOURNAL OF ELECTROCHEMISTRY 2012. [DOI: 10.1155/2012/271285] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Silicon carbide (SiC) is a promising material due to its unique property to adopt different crystalline polytypes which monitor the band gap and the electronic and optical properties. Despite being an indirect band gap semiconductor, SiC is used in several high-performance electronic and optical devices. SiC has been long recognized as one of the best biocompatible materials, especially in cardiovascular and blood-contacting implants and biomedical devices. In this paper, diverse role of SiC in its nanostructured form has been discussed. It is felt that further experimental and theoretical work would help to better understanding of the various properties of these nanostructures in order to realize their full potentials.
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16
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Wang M, Xiong S, Wu X, Chu PK. Effects of water molecules on photoluminescence from hierarchical peptide nanotubes and water probing capability. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2011; 7:2801-2807. [PMID: 22049551 DOI: 10.1002/smll.201100353] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Photoluminescence (PL) spectra reveal that deficiency of water molecules in the channel cores of bioinspired hierarchical diphenylalanine ( L -Phe- L -Phe, FF) peptide nanotubes (PNTs) not only modifies the bandgap of the subnanometer crystalline structure formed by the self-assembly process, but also induces a characteristic ultraviolet PL peak the position of which is linearly proportional to the number of water molecules in the PNTs. Addition or loss of water molecules gives rise to the UV PL redshift or blueshift. Density functional theory calculation also confirms that addition of water molecules to the PNTs causes splitting of the valence-band peak, which corresponds to the shift and splitting of the observed UV PL peak. Water molecules play an important role in the biological properties of FF PNTs and the results demonstrate that the PL spectra can be used to probe the number of water molecules bonded to the FF molecules.
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Affiliation(s)
- Minjie Wang
- Department of Physics, Nanjing University, Nanjing 210093, P. R. China
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17
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Yang N, Zhuang H, Hoffmann R, Smirnov W, Hees J, Jiang X, Nebel CE. Nanocrystalline 3C-SiC Electrode for Biosensing Applications. Anal Chem 2011; 83:5827-30. [DOI: 10.1021/ac201315q] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nianjun Yang
- Fraunhofer Institute for Applied Solid State Physics (IAF), Tullastrasse 72, Freiburg 79108, Germany
| | - Hao Zhuang
- Institute of Materials Engineering, University of Siegen, Paul-Bonatz-Strasse 9-11, Siegen 57076, Germany
| | - René Hoffmann
- Fraunhofer Institute for Applied Solid State Physics (IAF), Tullastrasse 72, Freiburg 79108, Germany
| | - Waldemar Smirnov
- Fraunhofer Institute for Applied Solid State Physics (IAF), Tullastrasse 72, Freiburg 79108, Germany
| | - Jakob Hees
- Fraunhofer Institute for Applied Solid State Physics (IAF), Tullastrasse 72, Freiburg 79108, Germany
| | - Xin Jiang
- Institute of Materials Engineering, University of Siegen, Paul-Bonatz-Strasse 9-11, Siegen 57076, Germany
| | - Christoph E. Nebel
- Fraunhofer Institute for Applied Solid State Physics (IAF), Tullastrasse 72, Freiburg 79108, Germany
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18
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Liu Y, Su K, Wang X, Wang Y, Zeng Q, Cheng L, Zhang L. An ONIOM study of H2O interacting with the C-terminated surface of silicon carbide. Chem Phys Lett 2010. [DOI: 10.1016/j.cplett.2010.10.059] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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19
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Fan J, Chu PK. Group IV nanoparticles: synthesis, properties, and biological applications. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2010; 6:2080-98. [PMID: 20730824 DOI: 10.1002/smll.201000543] [Citation(s) in RCA: 132] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
In this review, the emerging roles of group IV nanoparticles including silicon, diamond, silicon carbide, and germanium are summarized and discussed from the perspective of biologists, engineers, and medical practitioners. The synthesis, properties, and biological applications of these new nanomaterials have attracted great interest in the past few years. They have gradually evolved into promising biomaterials due to their innate biocompatibility; toxic ions are not released when they are used in vitro or in vivo, and their wide fluorescence spectral regions span the near-infrared, visible, and near-ultraviolet ranges. Additionally, they generally have good resistance against photobleaching and have lifetimes on the order of nanoseconds to microseconds, which are suitable for bioimaging. Some of the materials possess unique mechanical, chemical, or physical properties, such as ultrachemical and thermal stability, high hardness, high photostability, and no blinking. Recent data have revealed the superiority of these nanoparticles in biological imaging and drug delivery.
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Affiliation(s)
- Jiyang Fan
- Department of Physics, Southeast University, Nanjing 211189, PR China.
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20
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Fabbri F, Rossi F, Attolini G, Salviati G, Iannotta S, Aversa L, Verucchi R, Nardi M, Fukata N, Dierre B, Sekiguchi T. Enhancement of the core near-band-edge emission induced by an amorphous shell in coaxial one-dimensional nanostructure: the case of SiC/SiO2 core/shell self-organized nanowires. NANOTECHNOLOGY 2010; 21:345702. [PMID: 20683139 DOI: 10.1088/0957-4484/21/34/345702] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We report the influence of the native amorphous SiO(2) shell on the cathodoluminescence emission of 3C-SiC/SiO(2) core/shell nanowires. A shell-induced enhancement of the SiC near-band-edge emission is observed and studied as a function of the silicon dioxide thickness. Since the diameter of the investigated SiC cores rules out any direct bandgap optical transitions due to confinement effects, this enhancement is ascribed to a carrier diffusion from the shell to the core, promoted by the alignment of the SiO(2) and SiC bands in a type I quantum well. An accurate correlation between the optical emission and structural and SiO(2)-SiC interface properties is also reported.
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21
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Wang J, Xiong SJ, Wu XL, Li TH, Chu PK. Glycerol-bonded 3C-SiC nanocrystal solid films exhibiting broad and stable violet to blue-green emission. NANO LETTERS 2010; 10:1466-1471. [PMID: 20210349 DOI: 10.1021/nl100407d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We have produced glycerol-bonded 3C-SiC nanocrystal (NC) films, which when excited by photons of different wavelengths, produce strong and tunable violet to blue-green (360-540 nm) emission as a result of the quantum confinement effects rendered by the 3C-SiC NCs. The emission is so intense that the emission spots are visible to the naked eyes. The light emission is very stable and even after storing in air for more than six months, no intensity degradation can be observed. X-ray photoelectron spectroscopy and absorption fine structure measurements indicate that the Si-terminated NC surfaces are completely bonded to glycerol molecules. Calculations of geometry optimization and electron structures based on the density functional theory for 3C-SiC NCs with attached glycerol molecules show that these molecules are bonded on the NCs causing strong surface structural change, while the isolated levels in the conduction band of the bare 3C-SiC NCs are replaced with quasi-continuous bands that provide continuous tunability of the emitted light by changing the frequencies of exciting laser. As an application, we demonstrate the potential of using 3C-SiC NCs to fabricate full-color emitting solid films by incorporating porous silicon.
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Affiliation(s)
- J Wang
- National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing, People's Republic of China
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22
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Hu XL, Klimeš J, Michaelides A. Proton transfer in adsorbed water dimers. Phys Chem Chem Phys 2010; 12:3953-6. [DOI: 10.1039/b924422k] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Wu XL, Xiong SJ, Zhu J, Wang J, Shen JC, Chu PK. Identification of surface structures on 3C-SiC nanocrystals with hydrogen and hydroxyl bonding by photoluminescence. NANO LETTERS 2009; 9:4053-4060. [PMID: 19894694 DOI: 10.1021/nl902226u] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
SiC nanocrystals (NCs) exhibit unique surface chemistry and possess special properties. This provides the opportunity to design suitable surface structures by terminating the surface dangling bonds with different atoms thereby boding well for practical applications. In this article, we report the photoluminescence properties of 3C-SiC NCs in water suspensions with different pH values. Besides a blue band stemming from the quantum confinement effect, the 3C-SiC NCs show an additional photoluminescence band at 510 nm when the excitation wavelengths are longer than 350 nm. Its intensity relative to the blue band increases with the excitation wavelength. The 510 nm band appears only in acidic suspensions but not in alkaline ones. Fourier transform infrared, X-ray photoelectron spectroscopy, and X-ray absorption near-edge structure analyses clearly reveal that the 3C-SiC NCs in the water suspension have Si-H and Si-OH bonds on their surface, implying that water molecules only react with a Si-terminated surface. First-principle calculations suggest that the additional 510 nm band arises from structures induced by H(+) and OH(-) dissociated from water and attached to Si dimers on the modified (001) Si-terminated portion of the NCs. The size requirement is consistent with the observation that the 510 nm band can only be observed when the excitation wavelengths are relatively large, that is, excitation of bigger NCs.
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Affiliation(s)
- X L Wu
- National Laboratory of Solid State Microstructures, Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China
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24
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Fan J, Li H, Jiang J, So LKY, Lam YW, Chu PK. 3C-SiC nanocrystals as fluorescent biological labels. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2008; 4:1058-62. [PMID: 18618492 DOI: 10.1002/smll.200800080] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Affiliation(s)
- Jiyang Fan
- Department of Physics, Southeast University, Nanjing 211189, P.R. China.
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Abstract
We report on the interaction of water molecules with polar and nonpolar stoichiometric surfaces of cubic silicon carbide, as described by ab initio molecular dynamics at finite temperature. Our calculations show that, irrespective of coverage, in the gas phase water spontaneously dissociates on both polar Si-terminated (001) and nonpolar (110) surfaces, following similar mechanisms. The specific geometric arrangement of atoms on the outermost surface layer is responsible for water orientation and coordination and thus plays a major role in determining surface reactivity. This is found to be the case also for water on a computer-generated amorphous-SiC surface. In addition, from a macroscopic standpoint, the ability of the two crystalline surfaces with different polarities to induce water dissociation can be related to the similarities of their ionization potentials.
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26
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Kanai Y, Cicero G, Selloni A, Car R, Galli G. A Theoretical Study of Biotin Chemisorption on Si−SiC(001) Surfaces. J Phys Chem B 2005; 109:13656-62. [PMID: 16852711 DOI: 10.1021/jp051360h] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Biotin is a promising candidate for functionalization of semiconducting surfaces, given its strong, unmatched affinity to specific proteins such as streptavidin and avidin. Using density functional theory, we have carried out a theoretical investigation of the structural and electronic properties of biotin chemisorbed on a biocompatible substrate; in particular we have considered the clean and hydroxylated Si-SiC(001) surfaces. Our calculations show that, upon chemisorption, biotin retains the electronic properties responsible for its strong affinity to proteins. While the electronic states of the hydroxylated surface undergo negligible changes in the presence of the molecule, those of the clean surface are considerably affected.
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Affiliation(s)
- Yosuke Kanai
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA
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27
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Di Valentin C, Tilocca A, Selloni A, Beck TJ, Klust A, Batzill M, Losovyj Y, Diebold U. Adsorption of Water on Reconstructed Rutile TiO2(011)-(2×1): TiO Double Bonds and Surface Reactivity. J Am Chem Soc 2005; 127:9895-903. [PMID: 15998096 DOI: 10.1021/ja0511624] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recent combined experimental and theoretical studies (Beck et al., Phys. Rev. Lett. 2004, 93, 036104) have provided evidence for Ti=O double-bonded titanyl groups on the reconstructed rutile TiO(2)(011)-(2 x 1) surface. The adsorption of water on the same surface is now investigated to further probe the properties of these groups, as well as to confirm their existence. Ultraviolet photoemission experiments show that water is adsorbed in molecular form at a sample temperature of 110 K. At the same time, the presence of a 3sigma state in the photoemission spectra and work function measurements indicate a significant amount of hydroxyls within the first monolayer of water. At room temperature, scanning tunneling microscopy (STM) suggests that dissociated water is present, and about 30% of the surface active sites are hydroxylated. These findings are well explained by total energy density functional theory calculations and Car-Parrinello molecular dynamics simulations for water adsorption on the titanyl model of TiO(2)(011)-(2 x 1). The theoretical results show that a mixed molecular/dissociative layer is the most stable configuration in the monolayer regime at low temperatures, while complete dissociation takes place at 250 K. The arrangement of the protonated mono-coordinated oxygens in the mixed molecular/dissociated layer is consistent with the observed short-range order of the hydroxyls in the STM images.
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Affiliation(s)
- Cristiana Di Valentin
- Dipartimento di Scienza dei Materiali, Università degli Studi di Milano-Bicocca, 20125 Milano, Italy
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Cicero G, Catellani A. Towards SiC surface functionalization: An ab initio study. J Chem Phys 2005; 122:214716. [PMID: 15974771 DOI: 10.1063/1.1924546] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a microscopic model of the interaction and adsorption mechanism of simple organic molecules on SiC surfaces as obtained from ab initio molecular-dynamics simulations. Our results open the way to functionalization of silicon carbide, a leading candidate material for biocompatible devices.
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Affiliation(s)
- Giancarlo Cicero
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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Cicero G, Grossman JC, Catellani A, Galli G. Water at a Hydrophilic Solid Surface Probed by Ab initio Molecular Dynamics: Inhomogeneous Thin Layers of Dense Fluid. J Am Chem Soc 2005; 127:6830-5. [PMID: 15869306 DOI: 10.1021/ja042963u] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a microscopic model of the interface between liquid water and a hydrophilic, solid surface, as obtained from ab initio molecular dynamics simulations. In particular, we focused on the (100) surface of cubic SiC, a leading semiconductor candidate for biocompatible devices. Our results show that in the liquid in contact with the clean substrate, molecular dissociation occurs in a manner unexpectedly similar to that observed in the gas phase. After full hydroxylation takes place, the formation of a thin (approximately 3 A) interfacial layer is observed, which has higher density than bulk water and forms stable hydrogen bonds with the substrate. The presence of this thin layer points at rather weak effects on the structural properties of water induced by a one-dimensional confinement between approximately 1.3 nm hydrophilic substrates. In addition, our results show that the liquid does not uniformly wet the surface, but molecules preferably bind along directions parallel to the Si dimer rows.
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Affiliation(s)
- Giancarlo Cicero
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94550, USA.
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Cicero G, Galli G, Catellani A. Interaction of Water Molecules with SiC(001) Surfaces. J Phys Chem B 2004. [DOI: 10.1021/jp0471599] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Giancarlo Cicero
- Lawrence Livermore National Laboratory, Post Office Box 808, Livermore, California 94550
| | - Giulia Galli
- Lawrence Livermore National Laboratory, Post Office Box 808, Livermore, California 94550
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