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Two novel Anderson-type polyoxometalate based MnIII complexes constructed from pyrene derivatives: synthesis, photophysical, and electrochemical properties. Inorganica Chim Acta 2022. [DOI: 10.1016/j.ica.2022.121280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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2
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Song XN, Ji HY, Lin J, Wang RY, Ma Y, Wang CK. Geometric and electronic structures of pyrazine molecule chemisorbed on Si(100) surface by XPS and NEXAFS spectroscopy. CHINESE J CHEM PHYS 2020. [DOI: 10.1063/1674-0068/cjcp1910180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Xiu-neng Song
- School of Physics and Electronics, Shandong Normal University, Ji’nan 250014, China
| | - Huan-yu Ji
- School of Physics and Electronics, Shandong Normal University, Ji’nan 250014, China
| | - Juan Lin
- School of Physics and Electronics, Shandong Normal University, Ji’nan 250014, China
| | - Ruo-yu Wang
- School of Physics and Electronics, Shandong Normal University, Ji’nan 250014, China
| | - Yong Ma
- School of Physics and Electronics, Shandong Normal University, Ji’nan 250014, China
| | - Chuan-kui Wang
- School of Physics and Electronics, Shandong Normal University, Ji’nan 250014, China
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3
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Dalla Francesca K, Lenfant S, Laurans M, Volatron F, Izzet G, Humblot V, Methivier C, Guerin D, Proust A, Vuillaume D. Charge transport through redox active [H 7P 8W 48O 184] 33- polyoxometalates self-assembled onto gold surfaces and gold nanodots. NANOSCALE 2019; 11:1863-1878. [PMID: 30637426 DOI: 10.1039/c8nr09377f] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Polyoxometalates (POMs) are redox-active molecular oxides, which attract growing interest for their integration into nano-devices, such as high-density data storage non-volatile memories. In this work, we investigated the electrostatic deposition of the negatively charged [H7P8W48O184]33- POM onto positively charged 8-amino-1-octanethiol self-assembled monolayers (SAMs) preformed onto gold substrates or onto an array of gold nanodots. The ring-shaped [H7P8W48O184]33- POM was selected as an example of large POMs with high charge storage capacity. To avoid the formation of POM aggregates onto the substrates, which would introduce variability in the local electrical properties, special attention has to be paid to the preformed SAM seeding layer, which should itself be deprived of aggregates. Where necessary, rinsing steps were found to be crucial to eliminate these aggregates and to provide uniformly covered substrates for subsequent POM deposition and electrical characterizations. This especially holds for commercially available gold/glass substrates while these rinsing steps were not essential in the case of template stripped gold of very low roughness. Charge transport through the related molecular junctions and nanodot molecule junctions (NMJs) has been probed by conducting-AFM. We analyzed the current-voltage curves with different models: electron tunneling though the SAMs (Simmons model), transition voltage spectroscopy (TVS) method or molecular single energy level mediated transport (Landauer equation) and we discussed the energetics of the molecular junctions. We concluded to an energy level alignment of the alkyl spacer and POM lowest occupied molecular orbitals (LUMOs), probably due to dipolar effects.
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Affiliation(s)
- K Dalla Francesca
- Sorbonne Université, CNRS, Institut Parisien de Chimie Moléculaire, IPCM, 4 Place Jussieu, F-75005 Paris, France.
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4
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Laurans M, Dalla Francesca K, Volatron F, Izzet G, Guerin D, Vuillaume D, Lenfant S, Proust A. Molecular signature of polyoxometalates in electron transport of silicon-based molecular junctions. NANOSCALE 2018; 10:17156-17165. [PMID: 30187072 DOI: 10.1039/c8nr04946g] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Polyoxometalates (POMs) are unconventional electro-active molecules with a great potential for applications in molecular memories, providing efficient processing steps onto electrodes are available. The synthesis of the organic-inorganic polyoxometalate hybrids [PM11O39{Sn(C6H4)C[triple bond, length as m-dash]C(C6H4)N2}]3- (M = Mo, W) endowed with a remote diazonium function is reported together with their covalent immobilization onto hydrogenated n-Si(100) substrates. Electron transport measurements through the resulting densely-packed monolayers contacted with a mercury drop as a top electrode confirms their homogeneity. Adjustment of the current-voltage curves with the Simmon's equation gives a mean tunnel energy barrier ΦPOM of 1.8 eV and 1.6 eV, for the Silicon-Molecules-Metal (SMM) junctions based on the polyoxotungstates (M = W) and polyoxomolybdates (M = Mo), respectively. This follows the trend observed in the electrochemical properties of POMs in solution, the polyoxomolybdates being easier to reduce than the polyoxotungstates, in agreement with lowest unoccupied molecular orbitals (LUMOs) of lower energy. The molecular signature of the POMs is thus clearly identifiable in the solid-state electrical properties and the unmatched diversity of POM molecular and electronic structures should offer a great modularity.
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Affiliation(s)
- Maxime Laurans
- Sorbonne Université, CNRS, Institut Parisien de Chimie Moléculaire, IPCM, 4 Place Jussieu, F-75005 Paris, France.
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5
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Yates NDJ, Fascione MA, Parkin A. Methodologies for "Wiring" Redox Proteins/Enzymes to Electrode Surfaces. Chemistry 2018; 24:12164-12182. [PMID: 29637638 PMCID: PMC6120495 DOI: 10.1002/chem.201800750] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Indexed: 12/22/2022]
Abstract
The immobilization of redox proteins or enzymes onto conductive surfaces has application in the analysis of biological processes, the fabrication of biosensors, and in the development of green technologies and biochemical synthetic approaches. This review evaluates the methods through which redox proteins can be attached to electrode surfaces in a "wired" configuration, that is, one that facilitates direct electron transfer. The feasibility of simple electroactive adsorption onto a range of electrode surfaces is illustrated, with a highlight on the recent advances that have been achieved in biotechnological device construction using carbon materials and metal oxides. The covalent crosslinking strategies commonly used for the modification and biofunctionalization of electrode surfaces are also evaluated. Recent innovations in harnessing chemical biology methods for electrically wiring redox biology to surfaces are emphasized.
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Affiliation(s)
| | | | - Alison Parkin
- Department of ChemistryUniversity of YorkHeslington RoadYorkYO10 5DDUK
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Wang L, Yin P, Zhang J, Xiao F, Fang Z, Fu W, Wei Y, Xue S. An Unprecedented Class of Benzoyldiazenido-Functionalized Polyoxometalates with Enhanced Antitumour Activities. Eur J Inorg Chem 2017. [DOI: 10.1002/ejic.201700990] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Longsheng Wang
- Department of Chemistry; Tsinghua University; 100084 Beijing P R China
| | - Panchao Yin
- Department of Chemistry; Tsinghua University; 100084 Beijing P R China
| | - Jin Zhang
- Department of Chemistry; Tsinghua University; 100084 Beijing P R China
- State Key Laboratory of Natural and Biomimetic Drugs; Peking University; 100191 Beijing P R China
| | - Fengping Xiao
- Department of Chemistry; Tsinghua University; 100084 Beijing P R China
| | - Zhikun Fang
- Department of Chemistry; Shanghai Normal University; 200234 Shanghai P R China
| | - Weiwei Fu
- School of Chemistry and Materials; Hengyang Normal University; 421000 Hunan China
| | - Yongge Wei
- Department of Chemistry; Tsinghua University; 100084 Beijing P R China
- State Key Laboratory of Natural and Biomimetic Drugs; Peking University; 100191 Beijing P R China
- Department of Chemistry; Shanghai Normal University; 200234 Shanghai P R China
| | - Shijia Xue
- Department of Chemistry; Shanghai Normal University; 200234 Shanghai P R China
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Pan Y, Tao Y, Qin G, Fedoryshyn Y, Raja SN, Hu M, Degen CL, Poulikakos D. Surface Chemical Tuning of Phonon and Electron Transport in Free-Standing Silicon Nanowire Arrays. NANO LETTERS 2016; 16:6364-6370. [PMID: 27580070 DOI: 10.1021/acs.nanolett.6b02754] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We report electronic and phononic transport measurements of monocrystalline batch-fabricated silicon nanowire (SiNW) arrays functionalized with different surface chemistries. We find that hydrogen-terminated SiNWs prepared by vapor HF etching of native-oxide-covered devices show increased electrical conductivity but decreased thermal conductivity. We used the kinetic Monte Carlo method to solve the Boltzmann transport equation and also numerically examine the effect of phonon boundary scattering. Surface transfer doping of the SiNWs by cobaltocene or decamethylcobaltocene drastically improves the electrical conductivity by 2 to 4 orders of magnitude without affecting the thermal conductivity. The results showcase surface chemical control of nanomaterials as a potent pathway that can complement device miniaturization efforts in the quest for more efficient thermoelectric materials and devices.
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Affiliation(s)
- Ying Pan
- Laboratory of Thermodynamics in Emerging Technologies, Department of Mechanical and Process Engineering, ETH Zürich , Sonneggstrasse 3, 8092 Zürich, Switzerland
| | - Ye Tao
- Laboratory for Solid State Physics, Department of Physics, ETH Zürich , Otto-Stern-Weg 1, 8093 Zürich, Switzerland
| | - Guangzhao Qin
- Institute of Mineral Engineering, Division of Materials Science and Engineering, RWTH Aachen University , Mauerstrasse 5, 52064 Aachen, Germany
| | - Yuriy Fedoryshyn
- Institute of Electromagnetic Fields, Department of Information Technology and Electrical Engineering, ETH Zürich , Gloriastrasse 35, 8092 Zürich, Switzerland
| | - Shyamprasad N Raja
- Laboratory of Thermodynamics in Emerging Technologies, Department of Mechanical and Process Engineering, ETH Zürich , Sonneggstrasse 3, 8092 Zürich, Switzerland
| | - Ming Hu
- Institute of Mineral Engineering, Division of Materials Science and Engineering, RWTH Aachen University , Mauerstrasse 5, 52064 Aachen, Germany
- Aachen Institute for Advanced Study in Computational Engineering Science (AICES), RWTH Aachen University , Mauerstrasse 5, 52062 Aachen, Germany
| | - Christian L Degen
- Laboratory for Solid State Physics, Department of Physics, ETH Zürich , Otto-Stern-Weg 1, 8093 Zürich, Switzerland
| | - Dimos Poulikakos
- Laboratory of Thermodynamics in Emerging Technologies, Department of Mechanical and Process Engineering, ETH Zürich , Sonneggstrasse 3, 8092 Zürich, Switzerland
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8
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Izzet G, Volatron F, Proust A. Tailor-made Covalent Organic-Inorganic Polyoxometalate Hybrids: Versatile Platforms for the Elaboration of Functional Molecular Architectures. CHEM REC 2016; 17:250-266. [PMID: 27546462 DOI: 10.1002/tcr.201600092] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Indexed: 11/08/2022]
Abstract
Post-functionalization of organically modified polyoxometalates (POMs) is a powerful synthetic tool to devise functional building blocks for the rational elaboration of POM-based molecular materials. In this personal account we focus on iodoaryl-terminated POM platforms, describe reliable routes to the synthesis of covalent organic-inorganic POM-based hybrids and their integration into advanced molecular architectures or multi-scale assemblies as well as their immobilization onto surfaces. Valorisation of the remarkable redox properties of POMs in the fields of artificial synthesis and molecular electronic is especially considered.
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Affiliation(s)
- Guillaume Izzet
- Institut Parisien de Chimie Moléculaire UMR CNRS 8232, Sorbonne Universités, UPMC-Paris06, 4 Place Jussieu, F-75005, Paris, France
| | - Florence Volatron
- Institut Parisien de Chimie Moléculaire UMR CNRS 8232, Sorbonne Universités, UPMC-Paris06, 4 Place Jussieu, F-75005, Paris, France
| | - Anna Proust
- Institut Parisien de Chimie Moléculaire UMR CNRS 8232, Sorbonne Universités, UPMC-Paris06, 4 Place Jussieu, F-75005, Paris, France
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9
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Tao Y, Hauert R, Degen CL. Exclusively Gas-Phase Passivation of Native Oxide-Free Silicon(100) and Silicon(111) Surfaces. ACS APPLIED MATERIALS & INTERFACES 2016; 8:13157-13165. [PMID: 27153212 DOI: 10.1021/acsami.6b03326] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Reactions in the gas phase are of primary technological importance for applications in nano- and microfabrication technology and in the semiconductor industry. We present exclusively gas-phase protocols to chemically passivate oxide-free Si(111) and Si(100) surfaces with short-chain alkynes. The resulting surfaces showed equal or better oxidation resistance than most existing liquid-phase-derived surfaces and rivaled the outstanding stability of a full-coverage Si(111)-propenyl surface.1,2 The most stable surface (Si(111)-ethenyl) grew one-fifth of a monolayer of oxide (0.04 nm) after 1 month of air exposure. We monitored the regrowth of oxides on passivated Si(111) and Si(100) surfaces by X-ray photoelectron spectroscopy (XPS) and observed a significant crystal-orientation dependence of initial rates when total oxide thickness was below approximately one monolayer (0.2 nm). This difference was correlated with the desorption kinetics of residual surface Si-F bonds formed during HF treatment. We discuss applications of the technology and suggest future directions for process optimization.
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Affiliation(s)
- Ye Tao
- Department of Physics, ETH Zürich , 8093 Zürich, Switzerland
- Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Roland Hauert
- Empa, Swiss Federal Laboratories of Materials Science and Technology , 8600 Dübendorf, Switzerland
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10
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Affiliation(s)
- Bruno Fabre
- Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS/Université de Rennes 1, Matière Condensée et Systèmes Electroactifs MaCSE, 35042 Rennes Cedex, France
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11
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Balliou A, Papadimitropoulos G, Skoulatakis G, Kennou S, Davazoglou D, Gardelis S, Glezos N. Low-Dimensional Polyoxometalate Molecules/Tantalum Oxide Hybrids for Non-Volatile Capacitive Memories. ACS APPLIED MATERIALS & INTERFACES 2016; 8:7212-7220. [PMID: 26926392 DOI: 10.1021/acsami.5b11204] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Transition-metal-oxide hybrids composed of high surface-to-volume ratio Ta2O5 matrices and a molecular analogue of transition metal oxides, tungsten polyoxometalates ([PW12O40](3-)), are introduced herein as a charge storage medium in molecular nonvolatile capacitive memory cells. The polyoxometalate molecules are electrostatically self-assembled on a low-dimensional Ta2O5 matrix, functionalized with an aminosilane molecule with primary amines as the anchoring moiety. The charge trapping sites are located onto the metal framework of the electron-accepting molecular entities as well as on the molecule/oxide interfaces which can immobilize negatively charged mobile oxygen vacancies. The memory characteristics of this novel nanocomposite were tested using no blocking oxide for extraction of structure-specific characteristics. The film was formed on top of the 3.1 nm-thick SiO2/n-Si(001) substrates and has been found to serve as both SiO2/Si interface states' reducer (i.e., quality enhancer) and electron storage medium. The device with the polyoxometalates sandwiched between two Ta2O5 films results in enhanced internal scattering of carriers. Thanks to this, it exhibits a significantly larger memory window than the one containing the plain hybrid and comparable retention time, resulting in a memory window of 4.0 V for the write state and a retention time around 10(4) s without blocking medium. Differential distance of molecular trapping centers from the cell's gate and electronic coupling to the space charge region of the underlying Si substrate were identified as critical parameters for enhanced electron trapping for the first time in such devices. Implementing a numerical electrostatic model incorporating structural and electronic characteristics of the molecular nodes derived from scanning probe and spectroscopic characterization, we are able to interpret the hybrid's electrical response and gain some insight into the electrostatics of the trapping medium.
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Affiliation(s)
- Angelika Balliou
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos , Aghia Paraskevi, Athens 153 10, Greece
- Department of Chemical Sciences, School of Chemical Engineering, National Technical University of Athens , Iroon Polytexneiou 9, Athens 157 80, Greece
| | - Giorgos Papadimitropoulos
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos , Aghia Paraskevi, Athens 153 10, Greece
| | - George Skoulatakis
- Department of Chemical Engineering, University of Patras , University Campus, Patras 26504, Greece
| | - Stella Kennou
- Department of Chemical Engineering, University of Patras , University Campus, Patras 26504, Greece
| | - Dimitrios Davazoglou
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos , Aghia Paraskevi, Athens 153 10, Greece
| | - Spiros Gardelis
- Department of Solid State Physics, National and Kapodistrian University of Athens , University Campus, Zografos, Athens 157 84, Greece
| | - Nikos Glezos
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos , Aghia Paraskevi, Athens 153 10, Greece
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12
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Supersensitive fingerprinting of explosives by chemically modified nanosensors arrays. Nat Commun 2014; 5:4195. [PMID: 24960270 DOI: 10.1038/ncomms5195] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 05/22/2014] [Indexed: 11/09/2022] Open
Abstract
The capability to detect traces of explosives sensitively, selectively and rapidly could be of great benefit for applications relating to civilian national security and military needs. Here, we show that, when chemically modified in a multiplexed mode, nanoelectrical devices arrays enable the supersensitive discriminative detection of explosive species. The fingerprinting of explosives is achieved by pattern recognizing the inherent kinetics, and thermodynamics, of interaction between the chemically modified nanosensors array and the molecular analytes under test. This platform allows for the rapid detection of explosives, from air collected samples, down to the parts-per-quadrillion concentration range, and represents the first nanotechnology-inspired demonstration on the selective supersensitive detection of explosives, including the nitro- and peroxide-derivatives, on a single electronic platform. Furthermore, the ultrahigh sensitivity displayed by our platform may allow the remote detection of various explosives, a task unachieved by existing detection technologies.
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13
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Yaqub M, Walsh JJ, Keyes TE, Proust A, Rinfray C, Izzet G, McCormac T, Forster RJ. Electron transfer to covalently immobilized Keggin polyoxotungstates on gold. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:4509-4516. [PMID: 24670101 DOI: 10.1021/la4048648] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Spontaneously adsorbed monolayers have been formed on gold electrodes using a Keggin polyoxotungstate with covalently attached alkanethiol linkers of two different lengths. Films of both polyoxotungstates show two well-defined reduction processes associated with the polyoxotungstate centers where the ionic liquid, [BMIM][BF4], acts as supporting electrolyte. The surface coverages are both less than that expected for a close-packed monolayer. For the short and long linkers, the voltammetric response can be described in terms of the Butler-Volmer response involving a surface confined species using standard heterogeneous electron transfer rate constants of 170 and 140 s(-1) for the first reduction and 150 and 100 s(-1) for the second reduction processes, respectively. The rate of electron transfer to a solution phase redox probe, ferrocyanide, is significantly more sensitive to the length of the linker than the rate of electron transfer to the tungstate centers. This behavior probably arises due to potential-induced changes in the film structure.
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14
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Vasudevan S, Ghosh AW. Using room temperature current noise to characterize single molecular spectra. ACS NANO 2014; 8:2111-2117. [PMID: 24476317 DOI: 10.1021/nn404526w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We propose a way to use room temperature random telegraph noise to characterize single molecules adsorbed on a backgated silicon field-effect transistor. The overlap of molecule and silicon electronic wave functions generates a set of trap levels that impose their unique scattering signatures on the voltage-dependent current noise spectrum. Our results are based on numerical modeling of the current noise, obtained by coupling a density functional treatment of the trap placement within the silicon band gap, a quantum kinetic treatment of the output current, and a Monte Carlo evaluation of the trap occupancy under resonance. As an illustrative example, we show how we can extract molecule-specific "fingerprints" of four benzene-based molecules directly from a frequency-voltage colormap of the noise statistics. We argue that such a colormap carries detailed information about the trap dynamics at the Fermi energy, including the presence of correlated interactions, observed experimentally in backgated carbon nanotubes.
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Affiliation(s)
- Smitha Vasudevan
- Department of Electrical and Computer Engineering, University of Virginia , Charlottesville, Virginia 22904, United States
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15
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Gam Derouich S, Rinfray C, Izzet G, Pinson J, Gallet JJ, Kanoufi F, Proust A, Combellas C. Control of the grafting of hybrid polyoxometalates on metal and carbon surfaces: toward submonolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:2287-2296. [PMID: 24494799 DOI: 10.1021/la500067e] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A Keggin-type POM is attached to gold or glassy carbon surfaces by electro(chemical) or peptidic coupling. In addition to demonstrating the robust attachment of the POMs (by electrochemistry, XPS, and IRRAS), the surface concentration, layer thickness, and rate constant for electron transfer from the surface to the POMs have been measured. The use of such complementary techniques is mandatory to characterize the modified electrodes properly. Whatever the grafting method, experimental conditions are found to allow monolayer or submonolayer coverage. Besides covalently grafted species, additional electrostatically bonded POMs are present in the film. Cathodic polarization allows removing them to get a grafted film that is stable with time and potential, which is a requirement in the design of molecular memories.
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Affiliation(s)
- Sarra Gam Derouich
- Physicochimie des Electrolytes, Colloides et Sciences Analytiques, UMR CNRS 7195 - ESPCI ParisTech, 10 rue Vauquelin, 75231 Paris Cedex 05, France
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16
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Collins G, O'Dwyer C, Morris M, Holmes JD. Palladium-catalyzed coupling reactions for the functionalization of Si surfaces: superior stability of alkenyl monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:11950-11958. [PMID: 23968278 DOI: 10.1021/la402480f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Palladium-catalyzed Suzuki, Heck, and Sonogashira coupling reactions were studied as reaction protocols for organic modification of Si surfaces. These synthetically useful protocols allow for surface modification of alkene, alkyne, and halide terminated surfaces. Surface oxidation and metal contamination were assessed by X-ray photoelectron spectroscopy. The nature of the primary passivation layer was an important factor in the oxidation resistance of the Si surface during the secondary functionalization. Specifically, the use of alkynes as the primary functionalization layer gave superior stability compared to alkene analogues. The ability to utilize Pd-catalyzed coupling chemistries on Si surfaces opens great versatility for potential molecular and nanoscale electronics and sensing/biosensing applications.
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Affiliation(s)
- Gillian Collins
- Department of Chemistry and the Tyndall National Institute, University College Cork , Cork, Ireland
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17
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Rinfray C, Izzet G, Pinson J, Gam Derouich S, Ganem JJ, Combellas C, Kanoufi F, Proust A. Electrografting of Diazonium-Functionalized Polyoxometalates: Synthesis, Immobilisation and Electron-Transfer Characterisation from Glassy Carbon. Chemistry 2013; 19:13838-46. [DOI: 10.1002/chem.201302304] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Indexed: 12/21/2022]
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18
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Lorion MM, Matt B, Alves S, Proust A, Poli G, Oble J, Izzet G. Versatile Post-functionalization of Polyoxometalate Platforms By Using An Unprecedented Range of Palladium-Catalyzed Coupling Reactions. Chemistry 2013; 19:12607-12. [DOI: 10.1002/chem.201301694] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Indexed: 11/08/2022]
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19
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Wang B, Haick H. Effect of chain length on the sensing of volatile organic compounds by means of silicon nanowires. ACS APPLIED MATERIALS & INTERFACES 2013; 5:5748-56. [PMID: 23725353 DOI: 10.1021/am401265z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Molecularly modified silicon nanowire field effect transistors (SiNW FETs) are starting to appear as promising devices for sensing various volatile organic compounds (VOCs). Understanding the connection between the molecular layer structure attached to the SiNWs and VOCs is essential for the design of high performance sensors. Here, we explore the chain length influence of molecular layers on the sensing performance to polar and nonpolar VOCs. SiNW FETs were functionalized with molecular layers that have similar end (methyl) group and amide bridge bond, but differ in their alkyl chain lengths. The resulting devices were then exposed to polar and nonpolar VOCs in various concentrations. Our results showed that the sensing response to changing the threshold voltage (ΔVth) and changing the relative hole mobility (Δμh/μh-a) have a proportional relationship to the VOC concentration. On exposure to a specific VOC concentration, ΔVth response increased with the chain length of the molecular modification. In contrast, Δμh/μh-a did not exhibit any obvious reliance on the chain length of the molecular layer. Analysis of the responses with an electrostatic-based model suggests that the sensor response in ΔVth is dependent on the VOC concentration, VOC vapor pressure, VOC-molecular layer binding energy, and VOC adsorption-induced dipole moment changes of molecular layer.
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Affiliation(s)
- Bin Wang
- The Department of Chemical Engineering and Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
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20
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Wang B, Haick H. Effect of functional groups on the sensing properties of silicon nanowires toward volatile compounds. ACS APPLIED MATERIALS & INTERFACES 2013; 5:2289-2299. [PMID: 23452335 DOI: 10.1021/am4004649] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Molecular layers attached to a silicon nanowire field effect transistor (SiNW FET) can serve as antennas for signal transduction of volatile organic compounds (VOCs). Nevertheless, the mutual relationship between the molecular layers and VOCs is still a puzzle. In the present paper, we explore the effect of the molecular layer's end (functional) groups on the sensing properties of VOCs. Toward this end, SiNW FETs were modified with tailor-made molecular layers that have the same backbone but differ in their end groups. Changes in the threshold voltage (ΔVth) and changes in the mobility (Δμh) were then recorded upon exposure to various VOCs. Model-based analysis indicates that the interaction between molecular layers and VOCs can be classified to three main scenarios: (a) dipole-dipole interaction between the molecular layer and the polar VOCs; (b) induced dipole-dipole interaction between the molecular layers and the nonpolar VOCs; and (c) molecular layer tilt as a result of VOCs diffusion. Based on these scenarios, it is likely that the electron-donating/withdrawing properties of the functional groups control the dipole moment orientation of the adsorbed VOCs and, as a result, determine the direction (or sign) of the ΔVth. Additionally, it is likely the diffusion of VOCs into the molecular layer, determined by the type of functional groups, is the main reason for the Δμh responses. The reported findings are expected to provide an efficient way to design chemical sensors that are based on SiNW FETs to nonpolar VOCs, which do not exchange carriers with the molecular layers.
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Affiliation(s)
- Bin Wang
- The Department of Chemical Engineering and Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
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Peng W, Aksamija Z, Scott SA, Endres JJ, Savage DE, Knezevic I, Eriksson MA, Lagally MG. Probing the electronic structure at semiconductor surfaces using charge transport in nanomembranes. Nat Commun 2013; 4:1339. [DOI: 10.1038/ncomms2350] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 11/30/2012] [Indexed: 11/09/2022] Open
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22
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Wen S, Guan W, Su Z, Yan L, Sanvito S. First principle investigation of transport properties of Lindqvist derivatives based molecular junction. J Mol Graph Model 2012; 38:220-5. [DOI: 10.1016/j.jmgm.2012.05.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 05/19/2012] [Accepted: 05/22/2012] [Indexed: 10/28/2022]
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23
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Proust A, Matt B, Villanneau R, Guillemot G, Gouzerh P, Izzet G. Functionalization and post-functionalization: a step towards polyoxometalate-based materials. Chem Soc Rev 2012; 41:7605-22. [PMID: 22782306 DOI: 10.1039/c2cs35119f] [Citation(s) in RCA: 664] [Impact Index Per Article: 55.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Polyoxometalates (POMs) have remarkable properties and a great deal of potential to meet contemporary societal demands regarding health, environment, energy and information technologies. However, implementation of POMs in various functional architectures, devices or materials requires a processing step. Most developments have considered the exchange of POM counterions in an electrostatically driven approach: immobilization of POMs on electrodes and other surfaces including oxides, embedding in polymers, incorporation into Layer-by-Layer assemblies or Langmuir-Blodgett films and hierarchical self-assembly of surfactant-encapsulated POMs have thus been thoroughly investigated. Meanwhile, the field of organic-inorganic POM hybrids has expanded and offers the opportunity to explore the covalent approach for the organization or immobilization of POMs. In this critical review, we focus on the use of POM hybrids in selected fields of applications such as catalysis, energy conversion and molecular nanosciences and we endeavor to discuss the impact of the covalent approach compared to the electrostatic one. The synthesis of organic-inorganic POM hybrids starting from bare POMs, that is the direct functionalization of POMs, is well documented and reliable and efficient synthetic procedures are available. However, as the complexity of the targeted functional system increases a multi-step strategy relying on the post-functionalization of preformed hybrid POM platforms could prove more appealing. In the second part of this review, we thus survey the synthetic methodologies of post-functionalization of POMs and critically discuss the opportunities it offers compared to direct functionalization.
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Affiliation(s)
- Anna Proust
- Institut Parisien de Chimie Moléculaire, UMR CNRS 7201, UPMC Univ Paris 06, Université Pierre et Marie Curie, 4 place Jussieu, Case 42, 75252, Paris Cedex 05, France.
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24
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Gan L, Zhang D, Guo X. Electrochemistry: an efficient way to chemically modify individual monolayers of graphene. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2012; 8:1326-1330. [PMID: 22354846 DOI: 10.1002/smll.201102302] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 12/12/2011] [Indexed: 05/31/2023]
Abstract
Fast and efficient surface functionalization of graphene is achieved by the electrochemical formation of aryl radicals from diazonium salts under mild conditions. Precise control of the ratio of electron-deficient nitro groups to electron-rich amino groups is also demostrated, potentially resulting in the controllable tuning of the electrical properties of graphenes.
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Affiliation(s)
- Lin Gan
- Center for Nanochemistry, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, P R China
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Hao J, Zhang J, Yin P, Xiao Z, Xiao F, Wei Y. Unprecedented Organoimido-Derivatised Lacunary Polyoxometalates. Chemistry 2012; 18:2503-6. [DOI: 10.1002/chem.201103830] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Indexed: 11/10/2022]
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Gao J, Liu X, Liu Y, Yu L, Feng Y, Chen H, Li Y, Rakesh G, Huan CHA, Sum TC, Zhao Y, Zhang Q. Experimental and theoretical studies on pyrene-grafted polyoxometalate hybrid. Dalton Trans 2012; 41:12185-91. [DOI: 10.1039/c2dt31474f] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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27
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Camacho-Alanis F, Castaneda H, Zangari G, Swami NS. Electrochemical impedance study of GaAs surface charge modulation through the deprotonation of carboxylic acid monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:11273-11277. [PMID: 21859118 DOI: 10.1021/la2013107] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Modifications to the space charge region of p+ and p-GaAs due to surface charge modulation by the pH-induced deprotonation of bound carboxylic acid terminal monolayers were studied by electrochemical impedance spectroscopy and correlated to flat-band potential measurements from Mott-Schottky plots. We infer that the negative surface dipole formed on GaAs due to monolayer deprotonation causes an enhancement of the downward interfacial band bending. The space charge layer modifications were correlated to intermolecular electrostatic interactions and semiconductor depletion characteristics.
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Cummings SP, Savchenko J, Ren T. Functionalization of flat Si surfaces with inorganic compounds—Towards molecular CMOS hybrid devices. Coord Chem Rev 2011. [DOI: 10.1016/j.ccr.2010.12.030] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Henriksson A, Friedbacher G, Hoffmann H. Surface modification of silicon nanowires via copper-free click chemistry. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:7345-7348. [PMID: 21591646 DOI: 10.1021/la200951x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A two-step process based on copper-free click chemistry is described, by which the surface of silicon nanowires can be functionalized with specific organic substituents. A hydrogen-terminated nanowire surface is first primed with a monolayer of an α,ω-diyne and thereby turned into an alkyne-terminated, clickable platform, which is subsequently coupled with an overlayer of an organic azide carrying the desired terminal functionality. The reactive, electron-deficient character of the employed diyne enabled a quantitative coupling reaction at 50 °C without metal catalysis, which opens up a simple and versatile route for surface functionalization under mild conditions without any potentially harmful additives.
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Affiliation(s)
- Anders Henriksson
- Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9/163, A-1060 Wien, Austria
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Matt B, Renaudineau S, Chamoreau LM, Afonso C, Izzet G, Proust A. Hybrid polyoxometalates: Keggin and Dawson silyl derivatives as versatile platforms. J Org Chem 2011; 76:3107-12. [PMID: 21417425 DOI: 10.1021/jo102546v] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new series of polyoxometalate-based hybrids has been synthesized. These covalently linked organic-inorganic materials represent valuable elementary building blocks ready for postfunctionalization, using classical organic reactions and couplings. This approach is exemplified by the grafting of an organic chromophore via a Sonogashira coupling.
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Affiliation(s)
- B Matt
- Institut Parisien de Chimie Moléculaire, UMR CNRS 7201, Université Pierre et Marie Curie-Paris 06, 4 place Jussieu, Case 42, 75252 Paris Cedex 05, France
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31
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Dubey G, Rosei F, Lopinski GP. Highly sensitive electrical detection of TCNE on chemically passivated silicon-on-insulator. Chem Commun (Camb) 2011; 47:10593-5. [DOI: 10.1039/c1cc12504d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Gooding JJ, Ciampi S. The molecular level modification of surfaces: from self-assembled monolayers to complex molecular assemblies. Chem Soc Rev 2011; 40:2704-18. [DOI: 10.1039/c0cs00139b] [Citation(s) in RCA: 390] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Dubey G, Rosei F, Lopinski GP. Molecular modulation of conductivity on H-terminated silicon-on-insulator substrates. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2010; 6:2892-2899. [PMID: 21080387 DOI: 10.1002/smll.201001285] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The adsorption of a range of molecular species (water, pyridine, and ammonia) is found to reversibly modulate the conductivity of hydrogen-terminated silicon-on-insulator (H-SOI) substrates. Simultaneous sheet-resistance and Hall-effect measurements on moderately doped (10(15) cm(-3)) n- and p-type H-SOI samples mounted in a vacuum system are used to monitor the effect of gas exposure in the Torr range on the electrical-transport properties of these substrates. Reversible physisorption of "hole-trapping" species, such as pyridine (C(5)H(5)N) and ammonia (NH(3)) produces highly conductive minority-carrier channels (inversion) on p-type substrates, mimicking the action of a metallic gate in a field-effect transistor. The adsorption of these same molecules on n-type SOI induces strong electron-accumulation layers. Minority/majority channels are also formed upon controlled exposure to water vapor. These observations can be explained by a classical band-bending model, which considers the adsorbates as the source of a uniform surface charge ranging from +10(11) to +10(12)q cm(-2). These results demonstrate the utility of DC transport measurements of SOI platforms for studies of molecular adsorption and charge-transfer effects at semiconductor surfaces.
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Affiliation(s)
- Girjesh Dubey
- Steacie Institute for Molecular Sciences, National Research Council, 100 Sussex Drive, Ottawa, Ontario, K1A 0R6, Canada
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Ryu HJ, Aksamija Z, Paskiewicz DM, Scott SA, Lagally MG, Knezevic I, Eriksson MA. Quantitative determination of contributions to the thermoelectric power factor in Si nanostructures. PHYSICAL REVIEW LETTERS 2010; 105:256601. [PMID: 21231606 DOI: 10.1103/physrevlett.105.256601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Indexed: 05/30/2023]
Abstract
We report thermoelectric measurements on a silicon nanoribbon in which an integrated gate provides strong carrier confinement and enables tunability of the carrier density over a wide range. We find a significantly enhanced thermoelectric power factor that can be understood by considering its behavior as a function of carrier density. We identify the underlying mechanisms for the power factor in the nanoribbon, which include quantum confinement, low scattering due to the absence of dopants, and, at low temperatures, a significant phonon-drag contribution. The measurements set a target for what may be achievable in ultrathin nanowires.
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Affiliation(s)
- Hyuk Ju Ryu
- University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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Wu L, Camacho-Alanis F, Castaneda H, Zangari G, Swami N. Electrochemical impedance spectroscopy of carboxylic-acid terminal alkanethiol self assembled monolayers on GaAs substrates. Electrochim Acta 2010. [DOI: 10.1016/j.electacta.2010.08.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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36
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Miranda-Durán A, Cartoixà X, Cruz Irisson M, Rurali R. Molecular doping and subsurface dopant reactivation in si nanowires. NANO LETTERS 2010; 10:3590-3595. [PMID: 20734978 DOI: 10.1021/nl101894q] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Impurity doping in semiconductor nanowires, while increasingly well understood, is not yet controllable at a satisfactory degree. The large surface-to-volume area of these systems, however, suggests that adsorption of the appropriate molecular complexes on the wire sidewalls could be a viable alternative to conventional impurity doping. We perform first-principles electronic structure calculations to assess the possibility of n- and p-type doping of Si nanowires by exposure to NH(3) and NO(2). Besides providing a full rationalization of the experimental results recently obtained in mesoporous Si, our calculations show that while NH(3) is a shallow donor, NO(2) yields p-doping only when passive surface segregated B atoms are present.
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Affiliation(s)
- Alvaro Miranda-Durán
- Departament d'Enginyeria Electònica, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
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Shaya O, Amit I, Rosenwaks Y. The effect of nonideal polar monolayers on molecular gated transistors. ACS APPLIED MATERIALS & INTERFACES 2010; 2:2289-2292. [PMID: 20735099 DOI: 10.1021/am1003415] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Nonideal polar monolayers can induce a field-effect in molecular gated transistors. To quantify the magnitude of this phenomenon, we have calculated the effect of roughness and noncontinuity of such layers on the operation of hybrid silicon-on-insulator field-effect transistors. The results show that under most practical conditions, the nonideality of polar monolayers induces very small electric fields in the underlying transistor channel, and consequently a negligible gating effect.
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Affiliation(s)
- O Shaya
- School of Electrical Engineering, Faculty of Engineering, Tel-Aviv University, Ramat-Aviv 69978, Israel
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38
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Gatard S, Blanchard S, Schollhorn B, Gouzerh P, Proust A, Boubekeur K. Electroactive Benzothiazole Hydrazones and Their [Mo6O19]2− Derivatives: Promising Building Blocks for Conducting Molecular Materials. Chemistry 2010; 16:8390-9. [DOI: 10.1002/chem.201000427] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Sharma J, Chang HC, Tai Y. Discriminate crystallinities of tin doped indium oxide films on self-assembled monolayers modified glass substrates. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:8251-8255. [PMID: 20387823 DOI: 10.1021/la904654d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Tin doped indium oxide (ITO) films have generated tremendous research interest and received widespread applications in optoelectronic devices due to a good combination of desired optical and electrical properties. Their electrical properties vary depending on the crystallinity of the film. A good quality ITO film should have low resistivity, which can be achieved with highly crystalline films deposited at very high temperature. Thus, film quality is sensitive to the deposition conditions. Generally, low-temperature deposition of ITO results in poor quality films due to amorphous growth. In this study, we have demonstrated that crystallinity of the ITO films can be improved even at room temperature (RT) using self-assembled monolayers (SAMs) modified glass substrates. The present study demonstrates that SAM with -SH terminal group is necessary for the high-quality ITO growth, while SAMs with other terminal groups (-NH(2) and -CH(3)) generate ITO films with moderate crystallinity. Various properties of such films were investigated using X-ray diffraction, X-ray photoelectron depth profile, four-point probe, and Hall measurements. It is confirmed from such measurements that ITO film deposited on -SH terminated SAM substrate has excellent crystallinity, conductivity, and optical transmission.
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Affiliation(s)
- Jadab Sharma
- Department of Chemical Engineering, National Taiwan University of Science and Technology, 43 Keelung Road, Taipei 106, Taiwan
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Clavaguera S, Carella A, Caillier L, Celle C, Pécaut J, Lenfant S, Vuillaume D, Simonato JP. Sub-ppm Detection of Nerve Agents Using Chemically Functionalized Silicon Nanoribbon Field-Effect Transistors. Angew Chem Int Ed Engl 2010; 49:4063-6. [DOI: 10.1002/anie.201000122] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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41
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Clavaguera S, Carella A, Caillier L, Celle C, Pécaut J, Lenfant S, Vuillaume D, Simonato JP. Sub-ppm Detection of Nerve Agents Using Chemically Functionalized Silicon Nanoribbon Field-Effect Transistors. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201000122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Sinitskii A, Dimiev A, Corley DA, Fursina AA, Kosynkin DV, Tour JM. Kinetics of diazonium functionalization of chemically converted graphene nanoribbons. ACS NANO 2010; 4:1949-54. [PMID: 20345149 DOI: 10.1021/nn901899j] [Citation(s) in RCA: 144] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
We demonstrate that graphene nanoribbons (GNRs) produced by the oxidative unzipping of carbon nanotubes can be chemically functionalized by diazonium salts. We show that functional groups form a thin layer on a GNR and modify its electrical properties. The kinetics of the functionalization can be monitored by probing the electrical properties of GNRs, either in vacuum after the grafting, or in situ in the solution. We derive a simple kinetics model that describes the change in the electrical properties of GNRs. The reaction of GNRs with 4-nitrobenzene diazonium tetrafluoroborate is reasonably fast, such that >60% of the maximum change in the electrical properties is observed after less than 5 min of grafting at room temperature.
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Affiliation(s)
- Alexander Sinitskii
- Department of Chemistry, Rice University, MS 222, 6100 Main Street, Houston, Texas 77005, USA
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Corley DA, He T, Tour JM. Two-terminal molecular memories from solution-deposited C60 films in vertical silicon nanogaps. ACS NANO 2010; 4:1879-1888. [PMID: 20230044 DOI: 10.1021/nn901566v] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We demonstrate here two-terminal, charge-based memory from C60 films inside vertical 7 nm silicon nanogap devices. This testbed structure eliminated the possibility of metal migration in the nanostructure because the two electrodes are made solely of silicon; hence, the often troublesome and confusing possibility of filamentary metal formation is obviated. Saturated solutions of C60 in toluene, mesitylene, and 1-methylnaphthalene were each used to deposit these films at elevated temperatures. Electrical I-V measurements reveal a high yield (67%) of devices demonstrating bipolar, switchable hysteresis from both the mesitylene- and 1-methylnaphthalene-deposited devices, while the toluene-grafted devices display no such behavior. Pulse-based memory measurements of switching devices indicate high ON/OFF ratios (maximum approximately 1500), good stability (>100 cycles without device degradation) for molecular devices, and low operating currents (approximately 10(-11) A) in room temperature testing.
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Affiliation(s)
- David A Corley
- Department of Chemistry, Rice University, Houston, Texas 77005, USA
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Joo N, Renaudineau S, Delapierre G, Bidan G, Chamoreau LM, Thouvenot R, Gouzerh P, Proust A. Organosilyl/-germyl Polyoxotungstate Hybrids for Covalent Grafting onto Silicon Surfaces: Towards Molecular Memories. Chemistry 2010; 16:5043-51. [DOI: 10.1002/chem.200903336] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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45
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Capua E, Natan A, Kronik L, Naaman R. The molecularly controlled semiconductor resistor: how does it work? ACS APPLIED MATERIALS & INTERFACES 2009; 1:2679-83. [PMID: 20356142 DOI: 10.1021/am9005622] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
We examine the current response of molecularly controlled semiconductor devices to the presence of weakly interacting analytes. We evaluate the response of two types of devices, a silicon oxide coated silicon device and a GaAs/AlGaAs device, both coated with aliphatic chains and exposed to the same set of analytes. By comparing the device electrical response with contact potential difference and surface photovoltage measurements, we show that there are two mechanisms that may affect the underlying substrate, namely, formation of layers with a net dipolar moment and molecular interaction with surface states. We find that whereas the Si device response is mostly correlated to the analyte dipole, the GaAs device response is mostly correlated to interactions with surface states. Existence of a silicon oxide layer, whether native on the Si or deliberately grown on the GaAs, eliminates analyte interaction with the surface states.
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Affiliation(s)
- Eyal Capua
- Department of Chemical Physics, Weizmann Institute of Science, Rehovoth 76100, Israel
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Scott SA, Peng W, Kiefer AM, Jiang H, Knezevic I, Savage DE, Eriksson MA, Lagally MG. Influence of surface chemical modification on charge transport properties in ultrathin silicon membranes. ACS NANO 2009; 3:1683-1692. [PMID: 19499933 DOI: 10.1021/nn9000947] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Ultrathin silicon-on-insulator, composed of a crystalline sheet of silicon bounded by native oxide and a buried oxide layer, is extremely resistive because of charge trapping at the interfaces between the sheet of silicon and the oxide. After chemical modification of the top surface with hydrofluoric acid (HF), the sheet resistance drops to values below what is expected based on bulk doping alone. We explain this behavior in terms of surface-induced band structure changes combined with the effective isolation from bulk properties created by crystal thinness.
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He T, Corley DA, Lu M, Spigna NHD, He J, Nackashi DP, Franzon PD, Tour JM. Controllable Molecular Modulation of Conductivity in Silicon-Based Devices. J Am Chem Soc 2009; 131:10023-30. [DOI: 10.1021/ja9002537] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Tao He
- Departments of Chemistry, Computer Science, Mechanical Engineering, and Materials Science, and the Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005 and Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695
| | - David A. Corley
- Departments of Chemistry, Computer Science, Mechanical Engineering, and Materials Science, and the Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005 and Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695
| | - Meng Lu
- Departments of Chemistry, Computer Science, Mechanical Engineering, and Materials Science, and the Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005 and Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695
| | - Neil Halen Di Spigna
- Departments of Chemistry, Computer Science, Mechanical Engineering, and Materials Science, and the Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005 and Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695
| | - Jianli He
- Departments of Chemistry, Computer Science, Mechanical Engineering, and Materials Science, and the Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005 and Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695
| | - David P. Nackashi
- Departments of Chemistry, Computer Science, Mechanical Engineering, and Materials Science, and the Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005 and Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695
| | - Paul D. Franzon
- Departments of Chemistry, Computer Science, Mechanical Engineering, and Materials Science, and the Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005 and Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695
| | - James M. Tour
- Departments of Chemistry, Computer Science, Mechanical Engineering, and Materials Science, and the Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005 and Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27695
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Mischki TK, Lopinski GP, Wayner DDM. Evidence for initiation of thermal reactions of alkenes with hydrogen-terminated silicon by surface-catalyzed thermal decomposition of the reactant. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:5626-5630. [PMID: 19298049 DOI: 10.1021/la804210d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
New insights into the mechanism of thermal reactions of alkenes with hydrogen terminated silicon are presented. Scanning tunneling microscopy (STM) imaging at the early stages of the reaction of 1-decene with H/Si(111) at 150 degrees C confirm this reaction occurs via a propagating radical chain mechanism. In addition, evidence is presented for an initiation mechanism involving degradation of hydrocarbon molecules catalyzed by the silanol surface of Schlenk tubes commonly used in carrying out these reactions. Hydrogen-terminated silicon surfaces are found to be unstable in the "inert" solvent dodecane when heated at 150 degrees C in a Pyrex Schlenk tube. By contrast, the surfaces were significantly more stable at the same temperature when reactions were carried out in Teflon (polytetrafluoroethylene or PTFE). The thermal reaction of decene with H/Si(111) was found to proceed more rapidly in Pyrex than in PTFE, consistent with an impurity-based initiation mechanism.
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Affiliation(s)
- Trevor K Mischki
- Steacie Institute for Molecular Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario, K1A 0R6 Canada
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Lee K, Nair PR, Scott A, Alam MA, Janes DB. Device considerations for development of conductance-based biosensors. JOURNAL OF APPLIED PHYSICS 2009; 105:102046. [PMID: 24753627 PMCID: PMC3982583 DOI: 10.1063/1.3116630] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2008] [Accepted: 01/05/2009] [Indexed: 05/19/2023]
Abstract
Design and fabrication of electronic biosensors based on field-effect-transistor (FET) devices require understanding of interactions between semiconductor surfaces and organic biomolecules. From this perspective, we review practical considerations for electronic biosensors with emphasis on molecular passivation effects on FET device characteristics upon immobilization of organic molecules and an electrostatic model for FET-based biosensors.
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Goykhman I, Korbakov N, Bartic C, Borghs G, Spira ME, Shappir J, Yitzchaik S. Direct Detection of Molecular Biorecognition by Dipole Sensing Mechanism. J Am Chem Soc 2009; 131:4788-94. [DOI: 10.1021/ja809051p] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ilya Goykhman
- Institute of Chemistry, School of Engineering, Department of Neurobiology, The Hebrew University of Jerusalem, Safra Campus - Givat Ram, 91904, Jerusalem, Israel, and IMEC, MCP/ART, Cell Based Sensors & Circuits, Kapeldreef 75, 3001 Heverlee, Belgium
| | - Nina Korbakov
- Institute of Chemistry, School of Engineering, Department of Neurobiology, The Hebrew University of Jerusalem, Safra Campus - Givat Ram, 91904, Jerusalem, Israel, and IMEC, MCP/ART, Cell Based Sensors & Circuits, Kapeldreef 75, 3001 Heverlee, Belgium
| | - Carmen Bartic
- Institute of Chemistry, School of Engineering, Department of Neurobiology, The Hebrew University of Jerusalem, Safra Campus - Givat Ram, 91904, Jerusalem, Israel, and IMEC, MCP/ART, Cell Based Sensors & Circuits, Kapeldreef 75, 3001 Heverlee, Belgium
| | - Gustaaf Borghs
- Institute of Chemistry, School of Engineering, Department of Neurobiology, The Hebrew University of Jerusalem, Safra Campus - Givat Ram, 91904, Jerusalem, Israel, and IMEC, MCP/ART, Cell Based Sensors & Circuits, Kapeldreef 75, 3001 Heverlee, Belgium
| | - Micha E. Spira
- Institute of Chemistry, School of Engineering, Department of Neurobiology, The Hebrew University of Jerusalem, Safra Campus - Givat Ram, 91904, Jerusalem, Israel, and IMEC, MCP/ART, Cell Based Sensors & Circuits, Kapeldreef 75, 3001 Heverlee, Belgium
| | - Joseph Shappir
- Institute of Chemistry, School of Engineering, Department of Neurobiology, The Hebrew University of Jerusalem, Safra Campus - Givat Ram, 91904, Jerusalem, Israel, and IMEC, MCP/ART, Cell Based Sensors & Circuits, Kapeldreef 75, 3001 Heverlee, Belgium
| | - Shlomo Yitzchaik
- Institute of Chemistry, School of Engineering, Department of Neurobiology, The Hebrew University of Jerusalem, Safra Campus - Givat Ram, 91904, Jerusalem, Israel, and IMEC, MCP/ART, Cell Based Sensors & Circuits, Kapeldreef 75, 3001 Heverlee, Belgium
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