1
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Chatenet M, Pollet BG, Dekel DR, Dionigi F, Deseure J, Millet P, Braatz RD, Bazant MZ, Eikerling M, Staffell I, Balcombe P, Shao-Horn Y, Schäfer H. Water electrolysis: from textbook knowledge to the latest scientific strategies and industrial developments. Chem Soc Rev 2022; 51:4583-4762. [PMID: 35575644 PMCID: PMC9332215 DOI: 10.1039/d0cs01079k] [Citation(s) in RCA: 176] [Impact Index Per Article: 88.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Indexed: 12/23/2022]
Abstract
Replacing fossil fuels with energy sources and carriers that are sustainable, environmentally benign, and affordable is amongst the most pressing challenges for future socio-economic development. To that goal, hydrogen is presumed to be the most promising energy carrier. Electrocatalytic water splitting, if driven by green electricity, would provide hydrogen with minimal CO2 footprint. The viability of water electrolysis still hinges on the availability of durable earth-abundant electrocatalyst materials and the overall process efficiency. This review spans from the fundamentals of electrocatalytically initiated water splitting to the very latest scientific findings from university and institutional research, also covering specifications and special features of the current industrial processes and those processes currently being tested in large-scale applications. Recently developed strategies are described for the optimisation and discovery of active and durable materials for electrodes that ever-increasingly harness first-principles calculations and machine learning. In addition, a technoeconomic analysis of water electrolysis is included that allows an assessment of the extent to which a large-scale implementation of water splitting can help to combat climate change. This review article is intended to cross-pollinate and strengthen efforts from fundamental understanding to technical implementation and to improve the 'junctions' between the field's physical chemists, materials scientists and engineers, as well as stimulate much-needed exchange among these groups on challenges encountered in the different domains.
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Affiliation(s)
- Marian Chatenet
- University Grenoble Alpes, University Savoie Mont Blanc, CNRS, Grenoble INP (Institute of Engineering and Management University Grenoble Alpes), LEPMI, 38000 Grenoble, France
| | - Bruno G Pollet
- Hydrogen Energy and Sonochemistry Research group, Department of Energy and Process Engineering, Faculty of Engineering, Norwegian University of Science and Technology (NTNU) NO-7491, Trondheim, Norway
- Green Hydrogen Lab, Institute for Hydrogen Research (IHR), Université du Québec à Trois-Rivières (UQTR), 3351 Boulevard des Forges, Trois-Rivières, Québec G9A 5H7, Canada
| | - Dario R Dekel
- The Wolfson Department of Chemical Engineering, Technion - Israel Institute of Technology, Haifa, 3200003, Israel
- The Nancy & Stephen Grand Technion Energy Program (GTEP), Technion - Israel Institute of Technology, Haifa 3200003, Israel
| | - Fabio Dionigi
- Department of Chemistry, Chemical Engineering Division, Technical University Berlin, 10623, Berlin, Germany
| | - Jonathan Deseure
- University Grenoble Alpes, University Savoie Mont Blanc, CNRS, Grenoble INP (Institute of Engineering and Management University Grenoble Alpes), LEPMI, 38000 Grenoble, France
| | - Pierre Millet
- Paris-Saclay University, ICMMO (UMR 8182), 91400 Orsay, France
- Elogen, 8 avenue du Parana, 91940 Les Ulis, France
| | - Richard D Braatz
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Martin Z Bazant
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Department of Mathematics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA
| | - Michael Eikerling
- Chair of Theory and Computation of Energy Materials, Division of Materials Science and Engineering, RWTH Aachen University, Intzestraße 5, 52072 Aachen, Germany
- Institute of Energy and Climate Research, IEK-13: Modelling and Simulation of Materials in Energy Technology, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Iain Staffell
- Centre for Environmental Policy, Imperial College London, London, UK
| | - Paul Balcombe
- Division of Chemical Engineering and Renewable Energy, School of Engineering and Material Science, Queen Mary University of London, London, UK
| | - Yang Shao-Horn
- Research Laboratory of Electronics and Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Helmut Schäfer
- Institute of Chemistry of New Materials, The Electrochemical Energy and Catalysis Group, University of Osnabrück, Barbarastrasse 7, 49076 Osnabrück, Germany.
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2
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Zhang Y, Zhou N. Electrochemical Biosensors Based on Micro‐fabricated Devices for Point‐of‐Care Testing: A Review. ELECTROANAL 2021. [DOI: 10.1002/elan.202100281] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Yuting Zhang
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of Education School of Biotechnology Jiangnan University Wuxi 214122 China
| | - Nandi Zhou
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of Education School of Biotechnology Jiangnan University Wuxi 214122 China
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3
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Chattopadhyay S, Bandyopadhyay S, Dey A. Kinetic Isotope Effects on Electron Transfer Across Self-Assembled Monolayers on Gold. Inorg Chem 2021; 60:597-605. [PMID: 33411526 DOI: 10.1021/acs.inorgchem.0c02185] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Reactions requiring controlled delivery of protons and electrons are important in storage of energy in small molecules. While control over proton transfer can be achieved by installing appropriate chemical functionality in the catalyst, control of electron-transfer (ET) rates can be achieved by utilizing self-assembled monolayers (SAMs) on electrodes. Thus, a deeper understanding of the ET through SAM to an immobilized or covalently attached redox-active species is desirable. Long-range ET across several SAM-covered Au electrodes to covalently attached ferrocene is investigated using protonated and deuterated thiols (R-SH/R-SD). The rate of tunneling is measured using both chronoamperometry and cyclic voltammetry, and it shows a prominent kinetic isotope effect (KIE). The KIE is ∼2 (normal) for medium-chain-length thiols but ∼0.47 (inverse) for long-chain thiols. These results imply substantial contribution from the classical modes at the Au-(H)SR interface, which shifts substantially upon deuteration of the thiols, to the ET process. The underlying H/D KIE of these exchangeable thiol protons should be considered when analyzing solvent isotope effects in catalysis utilizing SAM.
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Affiliation(s)
- Samir Chattopadhyay
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, West Bengal
| | - Sabyasachi Bandyopadhyay
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, West Bengal
| | - Abhishek Dey
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, West Bengal
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4
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Liu XJ, Tang GS, Pan JQ, Ma CZ, Wan KN. A possible channel effect of the organics adsorbed to the electrode surface on interfacial electron transfer in the alkaline Pb electrodeposition process. NEW J CHEM 2021. [DOI: 10.1039/d1nj01124c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A possible electron transfer channel in solid–liquid interface.
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Affiliation(s)
- Xin-Jie Liu
- State Key Laboratory of Chemical Resource Engineering
- Beijing University of Chemical Technology
- Beijing 100029
- China
- Guangxi University of Science and Technology
| | - Guang-Shi Tang
- State Key Laboratory of Chemical Resource Engineering
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Jun-Qing Pan
- State Key Laboratory of Chemical Resource Engineering
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Chun-Ze Ma
- State Key Laboratory of Chemical Resource Engineering
- Beijing University of Chemical Technology
- Beijing 100029
- China
| | - Kang-Ni Wan
- State Key Laboratory of Chemical Resource Engineering
- Beijing University of Chemical Technology
- Beijing 100029
- China
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5
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Huang J. Mixed quantum-classical treatment of electron transfer at electrocatalytic interfaces: Theoretical framework and conceptual analysis. J Chem Phys 2020; 153:164707. [DOI: 10.1063/5.0009582] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Jun Huang
- College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China and School of Vehicle and Mobility, Tsinghua University, Beijing 100084, China
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6
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Gunasekaran S, Reed DA, Paley DW, Bartholomew AK, Venkataraman L, Steigerwald ML, Roy X, Nuckolls C. Single-Electron Currents in Designer Single-Cluster Devices. J Am Chem Soc 2020; 142:14924-14932. [PMID: 32809814 DOI: 10.1021/jacs.0c04970] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Atomically precise clusters can be used to create single-electron devices wherein a single redox-active cluster is connected to two macroscopic electrodes via anchoring ligands. Unlike single-electron devices comprising nanocrystals, these cluster-based devices can be fabricated with atomic precision. This affords an unprecedented level of control over the device properties. Herein, we design a series of cobalt chalcogenide clusters with varying ligand geometries and core nuclearities to control their current-voltage (I-V) characteristics in a scanning tunneling microscope-based break junction (STM-BJ) device. First, the device geometry is modified by precisely positioning junction-anchoring ligands on the surface of the cluster. We show that the I-V characteristics are independent of ligand placement, confirming a sequential, single-electron tunneling mechanism. Next, we chemically fuse two clusters to realize a larger cluster dimer that behaves as a single electronic unit, possessing a smaller reorganization energy and more accessible redox states than the monomeric analogues. As a result, dimer-based devices exhibit significantly higher currents and can even be pushed to current saturation at high bias. Owing to these controllable properties, single-cluster junctions serve as an excellent platform for exploring incoherent charge transport processes at the nanoscale. With this understanding, as well as properties such as nonlinear I-V characteristics and rectification, these molecular clusters may function as conductive inorganic nodes in new devices and materials.
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Affiliation(s)
- Suman Gunasekaran
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Douglas A Reed
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Daniel W Paley
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | | | - Latha Venkataraman
- Department of Chemistry, Columbia University, New York, New York 10027, United States.,Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, United States
| | - Michael L Steigerwald
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Xavier Roy
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Colin Nuckolls
- Department of Chemistry, Columbia University, New York, New York 10027, United States
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7
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Shermukhamedov SA, Nazmutdinov RR, Zinkicheva TT, Bronshtein MD, Zhang J, Mao B, Tian Z, Yan J, Wu DY, Ulstrup J. Electronic Spillover from a Metallic Nanoparticle: Can Simple Electrochemical Electron Transfer Processes Be Catalyzed by Electronic Coupling of a Molecular Scale Gold Nanoparticle Simultaneously to the Redox Molecule and the Electrode? J Am Chem Soc 2020; 142:10646-10658. [DOI: 10.1021/jacs.9b09362] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Shokirbek A. Shermukhamedov
- Kazan National Research Technological University, K. Marx Street, 68, 420015 Kazan, Republic of Tatarstan, Russian Federation
| | - Renat R. Nazmutdinov
- Kazan National Research Technological University, K. Marx Street, 68, 420015 Kazan, Republic of Tatarstan, Russian Federation
| | - Tamara T. Zinkicheva
- Kazan National Research Technological University, K. Marx Street, 68, 420015 Kazan, Republic of Tatarstan, Russian Federation
| | - Michael D. Bronshtein
- Kazan National Research Technological University, K. Marx Street, 68, 420015 Kazan, Republic of Tatarstan, Russian Federation
| | - Jingdong Zhang
- Department of Chemistry, Bldg. 207, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
| | - Bingwei Mao
- State Key Laboratory of Physical Chemistry of Solid Surfaces and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, People’s Republic of China
| | - Zhongqun Tian
- State Key Laboratory of Physical Chemistry of Solid Surfaces and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, People’s Republic of China
| | - Jiawei Yan
- State Key Laboratory of Physical Chemistry of Solid Surfaces and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, People’s Republic of China
| | - De-Yin Wu
- State Key Laboratory of Physical Chemistry of Solid Surfaces and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, People’s Republic of China
| | - Jens Ulstrup
- Kazan National Research Technological University, K. Marx Street, 68, 420015 Kazan, Republic of Tatarstan, Russian Federation
- Department of Chemistry, Bldg. 207, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
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8
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Taylor NB, Kassal I. Generalised Marcus theory for multi-molecular delocalised charge transfer. Chem Sci 2018; 9:2942-2951. [PMID: 29732078 PMCID: PMC5915794 DOI: 10.1039/c8sc00053k] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 02/11/2018] [Indexed: 01/07/2023] Open
Abstract
Transfer of charges delocalised over multiple molecules can be described using the properties of the component molecules.
Although Marcus theory is widely used to describe charge transfer in molecular systems, in its usual form it is restricted to transfer from one molecule to another. If a charge is delocalised across multiple donor molecules, this approach requires us to treat the entire donor aggregate as a unified supermolecule, leading to potentially expensive quantum-chemical calculations and making it more difficult to understand how the aggregate components contribute to the overall transfer. Here, we show that it is possible to describe charge transfer between groups of molecules in terms of the properties of the constituent molecules and couplings between them, obviating the need for expensive supermolecular calculations. We use the resulting theory to show that charge delocalisation between molecules in either the donor or acceptor aggregates can enhance the rate of charge transfer through a process we call supertransfer (or suppress it through subtransfer). The rate can also be enhanced above what is possible with a single donor and a single acceptor by judiciously tuning energy levels and reorganisation energies. We also describe bridge-mediated charge transfer between delocalised molecular aggregates. The equations of generalised Marcus theory are in closed form, providing qualitative insight into the impact of delocalisation on charge dynamics in molecular systems.
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Affiliation(s)
- Natasha B Taylor
- Centre for Engineered Quantum Systems and School of Mathematics and Physics , The University of Queensland , Queensland 4072 , Australia
| | - Ivan Kassal
- Centre for Engineered Quantum Systems and School of Mathematics and Physics , The University of Queensland , Queensland 4072 , Australia.,The University of Sydney Nano Institute and School of Chemistry , The University of Sydney , NSW 2006 , Australia .
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9
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10
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Artés JM, López-Martínez M, Díez-Pérez I, Sanz F, Gorostiza P. Nanoscale charge transfer in redox proteins and DNA: Towards biomolecular electronics. Electrochim Acta 2014. [DOI: 10.1016/j.electacta.2014.05.089] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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11
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Alvarez-Paggi D, Zitare U, Murgida DH. The role of protein dynamics and thermal fluctuations in regulating cytochrome c/cytochrome c oxidase electron transfer. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1196-207. [PMID: 24502917 DOI: 10.1016/j.bbabio.2014.01.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 01/22/2014] [Accepted: 01/28/2014] [Indexed: 01/06/2023]
Abstract
In this overview we present recent combined electrochemical, spectroelectrochemical, spectroscopic and computational studies from our group on the electron transfer reactions of cytochrome c and of the primary electron acceptor of cytochrome c oxidase, the CuA site, in biomimetic complexes. Based on these results, we discuss how protein dynamics and thermal fluctuations may impact on protein ET reactions, comment on the possible physiological relevance of these results, and finally propose a regulatory mechanism that may operate in the Cyt/CcO electron transfer reaction in vivo. This article is part of a Special Issue entitled: 18th European Bioenergetic Conference.
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Affiliation(s)
- Damian Alvarez-Paggi
- INQUIMAE-CONICET, Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, pab. 2, piso 3, C1428EHA Buenos Aires, Argentina
| | - Ulises Zitare
- INQUIMAE-CONICET, Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, pab. 2, piso 3, C1428EHA Buenos Aires, Argentina
| | - Daniel H Murgida
- INQUIMAE-CONICET, Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, pab. 2, piso 3, C1428EHA Buenos Aires, Argentina.
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12
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13
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Artés JM, López-Martínez M, Giraudet A, Díez-Pérez I, Sanz F, Gorostiza P. Current–Voltage Characteristics and Transition Voltage Spectroscopy of Individual Redox Proteins. J Am Chem Soc 2012. [DOI: 10.1021/ja3080242] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Juan M. Artés
- Institute for Bioengineering of Catalonia (IBEC), Baldiri Reixac 15-21, 08028 Barcelona,
Spain
| | | | - Arnaud Giraudet
- Institute for Bioengineering of Catalonia (IBEC), Baldiri Reixac 15-21, 08028 Barcelona,
Spain
| | - Ismael Díez-Pérez
- Institute for Bioengineering of Catalonia (IBEC), Baldiri Reixac 15-21, 08028 Barcelona,
Spain
- Physical Chemistry
Department, University of Barcelona (UB),
Martí i Franquès
1-11, Barcelona 08028, Spain
| | - Fausto Sanz
- Institute for Bioengineering of Catalonia (IBEC), Baldiri Reixac 15-21, 08028 Barcelona,
Spain
- Physical Chemistry
Department, University of Barcelona (UB),
Martí i Franquès
1-11, Barcelona 08028, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 50018 Zaragoza, Spain
| | - Pau Gorostiza
- Institute for Bioengineering of Catalonia (IBEC), Baldiri Reixac 15-21, 08028 Barcelona,
Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 50018 Zaragoza, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), 08010 Barcelona,
Spain
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14
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Suwatchara D, Rees NV, Henstridge MC, Laborda E, Compton RG. Molecular insights into electron transfer processes via variable temperature cyclic voltammetry. Application of the asymmetric Marcus–Hush model. J Electroanal Chem (Lausanne) 2012. [DOI: 10.1016/j.jelechem.2012.09.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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15
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Salvatore P, Glargaard Hansen A, Moth-Poulsen K, Bjørnholm T, John Nichols R, Ulstrup J. Voltammetry and in situscanning tunnelling spectroscopy of osmium, iron, and ruthenium complexes of 2,2′:6′,2′′-terpyridine covalently linked to Au(111)-electrodes. Phys Chem Chem Phys 2011; 13:14394-403. [DOI: 10.1039/c1cp21197h] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Li Z, Liu Y, Mertens SFL, Pobelov IV, Wandlowski T. From Redox Gating to Quantized Charging. J Am Chem Soc 2010; 132:8187-93. [DOI: 10.1021/ja102754n] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Zhihai Li
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland, and Institute of Bio- and Nanosystems IBN 3 and Center of Nanoelectronic Systems, for Informational Technology, Research Center Jülich, D-52425 Jülich, Germany
| | - Yaqing Liu
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland, and Institute of Bio- and Nanosystems IBN 3 and Center of Nanoelectronic Systems, for Informational Technology, Research Center Jülich, D-52425 Jülich, Germany
| | - Stijn F. L. Mertens
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland, and Institute of Bio- and Nanosystems IBN 3 and Center of Nanoelectronic Systems, for Informational Technology, Research Center Jülich, D-52425 Jülich, Germany
| | - Ilya V. Pobelov
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland, and Institute of Bio- and Nanosystems IBN 3 and Center of Nanoelectronic Systems, for Informational Technology, Research Center Jülich, D-52425 Jülich, Germany
| | - Thomas Wandlowski
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland, and Institute of Bio- and Nanosystems IBN 3 and Center of Nanoelectronic Systems, for Informational Technology, Research Center Jülich, D-52425 Jülich, Germany
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17
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Li JF, Huang YF, Duan S, Pang R, Wu DY, Ren B, Xu X, Tian ZQ. SERS and DFT study of water on metal cathodes of silver, gold and platinum nanoparticles. Phys Chem Chem Phys 2010; 12:2493-502. [DOI: 10.1039/b919266b] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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18
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Vollmer E, Kordel M, Koslowski T. Variational Approach to Electron Transfer in Bridged Diruthenium Complexes. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zpch.218.5.611.30501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
In this work, we address the energetics of electron transfer in bridged diruthenium complexes from a theoretical and numerical perspective. The electronic structure of the bridged complexes is described by a tight-binding Hamiltonian, which is extended by an on-site spin pairing energy. The coupling of the system to a polarizable solvent is taken into account by a nonretarded reaction field. The resulting nonlinear Hamiltonian is solved within the Hartree–Fock mean-field approximation, and the emerging potential energy surface is analysed using Marcus´ theory of electron transfer reactions. For the systems studied here, the charge transfer rate depends on the chemical nature of the bridge rather than the intermetal distance. We discuss the special nature of the Creutz–Taube cation, which is on the border of charge delocalization.
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20
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Pobelov IV, Li Z, Wandlowski T. Electrolyte Gating in Redox-Active Tunneling Junctions—An Electrochemical STM Approach. J Am Chem Soc 2008; 130:16045-54. [DOI: 10.1021/ja8054194] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ilya V. Pobelov
- Department of Chemistry and Biochemistry, University of Bern, CH-3012 Bern, Switzerland, and Institute of Bio- and Nanosystems IBN 3 and Center of Nanoelectronic Systems for Informational Technology, Research Center Jülich, D-52425 Jülich, Germany
| | - Zhihai Li
- Department of Chemistry and Biochemistry, University of Bern, CH-3012 Bern, Switzerland, and Institute of Bio- and Nanosystems IBN 3 and Center of Nanoelectronic Systems for Informational Technology, Research Center Jülich, D-52425 Jülich, Germany
| | - Thomas Wandlowski
- Department of Chemistry and Biochemistry, University of Bern, CH-3012 Bern, Switzerland, and Institute of Bio- and Nanosystems IBN 3 and Center of Nanoelectronic Systems for Informational Technology, Research Center Jülich, D-52425 Jülich, Germany
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21
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Duque JG, Pasquali M, Schmidt HK. Antenna Chemistry with Metallic Single-Walled Carbon Nanotubes. J Am Chem Soc 2008; 130:15340-7. [DOI: 10.1021/ja803300u] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Juan G. Duque
- Department of Chemical and Biomolecular Engineering and Department of Chemistry, The Smalley Institute for Nanoscale Science & Technology, Rice University, 6100 South Main, Houston, Texas 77005
| | - Matteo Pasquali
- Department of Chemical and Biomolecular Engineering and Department of Chemistry, The Smalley Institute for Nanoscale Science & Technology, Rice University, 6100 South Main, Houston, Texas 77005
| | - Howard K. Schmidt
- Department of Chemical and Biomolecular Engineering and Department of Chemistry, The Smalley Institute for Nanoscale Science & Technology, Rice University, 6100 South Main, Houston, Texas 77005
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22
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Medvedev IG. Effect of the density of the electronic states at the valence orbital of the bridge redox molecule on the dependence of the tunnel current on the overvoltage in the case of fully adiabatic electron transition. Electrochim Acta 2008. [DOI: 10.1016/j.electacta.2008.04.031] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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23
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24
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Medvedev IG. The theory of in situ scanning tunneling microscopy of redox molecules in the case of the fully adiabatic electron transitions. J Electroanal Chem (Lausanne) 2007. [DOI: 10.1016/j.jelechem.2006.05.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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25
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Härtl A, Garrido JA, Nowy S, Zimmermann R, Werner C, Horinek D, Netz R, Stutzmann M. The Ion Sensitivity of Surface Conductive Single Crystalline Diamond. J Am Chem Soc 2007; 129:1287-92. [PMID: 17263412 DOI: 10.1021/ja066543b] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Charge build-up at the solid/aqueous interface is a ubiquitous phenomenon that determines the properties of interfacial electrical double layers. Due to its unique properties, the surface of diamond offers an attractive platform to investigate charging mechanisms in aqueous solutions. We investigate the surface charge by studying the ion sensitivity of H-terminated single crystalline diamond surface conductive layers. The effect of monovalent and divalent salts has been probed at different pH values. For a pH above 3.5, increasing the ionic strength results in a decrease of the surface conductivity, in contrast to the results obtained for pH below 3.5. Electrokinetic experiments are in good agreement with the surface conductivity measurements, showing an isoelectric point at pH 3.5 for the H-terminated diamond surface. We discuss the results in terms of the Coulombic screening by electrolyte ions of the surface potential, which is induced by a pH-dependent surface charge. The origin of this surface charge is discussed in terms of charge regulation by amphoteric hydroxyl surface groups and unsymmetrical adsorption of hydroxide and hydronium ions induced by the hydrophobic nature of the H-terminated diamond surface. This surface charge can have important consequences for processes governed by the diamond/aqueous interface, such as electron transfer to charged redox molecules, adsorption of charged molecules and proteins, and ion sensitivity.
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Affiliation(s)
- Andreas Härtl
- Walter Schottky Institut, Technische Universität München, Garching, Germany
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O'Boyle NM, Albrecht T, Murgida DH, Cassidy L, Ulstrup J, Vos JG. A Density Functional Theory Study of the Electronic Properties of Os(II) and Os(III) Complexes Immobilized on Au(111). Inorg Chem 2006; 46:117-24. [PMID: 17198419 DOI: 10.1021/ic060903e] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present a density functional theory (DFT) study of an osmium polypyridyl complex adsorbed on Au(111). The osmium polypyridyl complex [Os(bpy)2(P0P)Cl]n+ [bpy is 2,2'-bipyridine, P0P is 4,4'-bipyridine, n = 1 for osmium(II), and n = 2 for osmium(III)] is bound to the surface through the free nitrogen of the P0P ligand. The calculations illuminate electronic properties relevant to recent comprehensive characterization of this class of osmium complexes by electrochemistry and electrochemical scanning tunneling microscopy. The optimized structures for the compounds are in close agreement with crystallographic structures reported in the literature. Oxidation of the complex has little effect on these structural features, but there is a substantial reordering of the electronic energy levels with corresponding changes in the electron density. Significantly, the highest occupied molecular orbital shifts from the metal center to the P0P ligand. The surface is modeled by a cluster of 28 gold atoms and gives a good description of the effect of immobilization on the electronic properties of the complexes. The results show that the coupling between the immobilized complex and the gold surface involves electronic polarization at the adsorbate/substrate interface rather than the formation of a covalent bond. However, the cluster is too small to fully represent bulk gold with the result that, contrary to what is experimentally observed, the DFT calculation predicts that the gold surface is more easily oxidized than the osmium(II) complex.
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Affiliation(s)
- Noel M O'Boyle
- National Centre for Sensor Research, School of Chemical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland.
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Krivenko AG, Kurmaz VA. Thermodynamic and kinetic characteristics of intermediates of electrode reactions. Comparative laser photoemission study of the kinetics of electron transfer for certain alkylaryl and alkylhalide radicals. RUSS J ELECTROCHEM+ 2006. [DOI: 10.1134/s1023193506020017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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28
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Albrecht T, Moth-Poulsen K, Christensen JB, Guckian A, Bjørnholm T, Vos JG, Ulstrup J. In situscanning tunnelling spectroscopy of inorganic transition metal complexes. Faraday Discuss 2006; 131:265-79; discussion 307-24. [PMID: 16512377 DOI: 10.1039/b505451f] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Redox molecules with equilibrium potentials suitable for electrochemical control offer perspectives in nanoscale and single-molecule electronics. This applies to molecular but also towards higher sophistication such as transistor or diode function. Most recent nanoscale or single-molecule functional systems are, however, fraught with operational limitations such as cryogenic temperatures and ultra-high vacuum, or lack of electrochemical potential control. We report here cyclic voltammetry (CV) using single-crystal Au(111)- and Pt(111)-electrodes and electrochemical in situ scanning tunnelling microscopy (STM) of a class of Os(II)/(III)- and Co(II)/(III)-complexes, the former novel molecular electronics. The complexes are robust, with ligand groups suitable for linking the complexes to the Au(111)- and Pt(111)-surfaces via N- and S-donor atoms. The data reflect monolayer behaviour. Interfacial ET of the Os-complexes is fast, kET(0) > or = 10(6) s(-1), while the Co-complex reacts much more slowly, kET(0) approximately (1-3) x 10(3) s(-1). In STM of the Os-complexes shows a maximum in the tunnelling current/overpotential relation at constant bias voltage with up to 50-fold current rise. The peak position systematically the bias voltage and equilibrium potential, in keeping with theoretical frames for two-step electron transfer (ET) of in situ STM of redox molecules. The molecular conductivity behaves broadly similarly. The Co-complex also shows a tunnelling spectroscopic feature but much weaker than the Os-complexes. This can be ascribed much smaller interfacial ET rate constant, again caused by large intramolecular nuclear reorganization and weak electronic coupling to the substrate electrode. Overall the has mapped the properties of target molecules needed for stable electronic switching, possible importance in molecular electronics towards the single-molecule level, in room temperature condensed matter environment.
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Affiliation(s)
- Tim Albrecht
- Technical University of Denmark (DTU), Dept. Chemistry, Nano-DTU, Kemitorvet, Bldg. 207, Dk-2800, Kgs Lyngby, Denmark
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Li Z, Han B, Meszaros G, Pobelov I, Wandlowski T, Błaszczyk A, Mayor M. Two-dimensional assembly and local redox-activity of molecular hybrid structures in an electrochemical environment. Faraday Discuss 2006; 131:121-43; discussion 205-20. [PMID: 16512368 DOI: 10.1039/b506623a] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The self-assembly and redox-properties of two viologen derivatives, N-hexyl-N'-(6-thiohexyl)-4,4'-bipyridinium bromide (HS-6V6-H) and N,N'-bis(6-thiohexyl)-4,4'-bipyridinium bromide (HS-6V6-SH), immobilized on Au(lll)-(1 x 1) macro-electrodes were investigated by cyclic voltammetry, surface enhanced infrared spectroscopy (SEIRAS) and in situ scanning tunneling microscopy (STM). Depending on the assembly conditions one could distinguish three different types of adlayers for both viologens: a low coverage disordered and an ordered "striped" phase of flat oriented molecules as well as a high coverage monolayer composed of tilted viologen moieties. Both molecules, HS-6V6-H and HS-6V6-SH, were successfully immobilized on Au(poly) nano-electrodes, which gave a well-defined redox-response in the lower pA-current range. An in situ STM configuration was employed to explore electron transport properties of single molecule junctions Au(T)/HS-6V6-SH(HS-6V6-H)/Au(S). The observed sigmoidal potential dependence, measured at variable substrate potential E(S) and at constant bias voltage (E(T) - E(S)), was attributed to electronic structure changes of the viologen moiety during the one-electron reduction/re-oxidation process V2+ < -- > V+*. Tunneling experiments in asymmetric, STM-based junctions Au(T)-S-6V6-H/Au(S) revealed current (i(T))-voltage (E(T)) curves with a maximum located at the equilibrium potential of the redox-process V2+ < -- > V+*. The experimental i(T)--E(T) characteristics of the HS-6V6-H-modified tunneling junction were tentatively attributed to a sequential two-step electron transfer mechanism.
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Affiliation(s)
- Z Li
- Institute of Surfaces and Interfaces ISG 3 and cni, Research Center Jülich GmH, D-52425 Jülich, Germany
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Effect of preparation procedure of Iro2–Nb2o5 anodes on surface and electrocatalytic properties. J APPL ELECTROCHEM 2005. [DOI: 10.1007/s10800-005-4720-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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31
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Yusipovich AI, Vassiliev SY. Voltage-Height Spectroscopy in the Ex Situ Configuration of a Scanning Tunneling Microscope. RUSS J ELECTROCHEM+ 2005. [DOI: 10.1007/s11175-005-0097-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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32
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Zhang J, Chi Q, Albrecht T, Kuznetsov AM, Grubb M, Hansen AG, Wackerbarth H, Welinder AC, Ulstrup J. Electrochemistry and bioelectrochemistry towards the single-molecule level: Theoretical notions and systems. Electrochim Acta 2005. [DOI: 10.1016/j.electacta.2004.12.044] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Zhang J, Guo SX, Bond AM, Honeychurch MJ, Oldham KB. Novel Kinetic and Background Current Selectivity in the Even Harmonic Components of Fourier Transformed Square-Wave Voltammograms of Surface-Confined Azurin. J Phys Chem B 2005; 109:8935-47. [PMID: 16852063 DOI: 10.1021/jp044614s] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Fourier transform analysis of ramped square-wave voltammograms indicates the availability of a novel form of kinetic selectivity for surface-confined electron-transfer processes. Thus, for all the even harmonic components, quasi-reversible processes are sensitive to the surface coverage, the reversible potential, the electron-transfer rate constant (k(0')), and the electron-transfer coefficient (alpha), as well as to the amplitude (DeltaE) and frequency (f) of the square wave and dc scan rate. Additionally, it is insensitive to background capacitance current. In contrast, reversible processes and background currents are predicted to be absent from the even harmonics and only detectable in the odd harmonic components. The square-wave voltammetry of the surface-confined quasi-reversible azurin process azurin[Cu(II)] + e(-) right arrow over left arrow azurin[Cu(I)] at a paraffin-impregnated graphite electrode has been employed as a model system to test theoretical predictions. Most voltammetric characteristics of the even harmonic components obtained from the Fourier analysis are consistent with electrode kinetic values of k(0') = 90 s(-1) and alpha = 0.48, although some nonideality possibly due to kinetic dispersion also is apparent. Conditions also have been determined under which a readily generated waveform constructed from the Fourier series of sine waves produces voltammograms that are essentially indistinguishable from those predicted when an ideal square wave is employed.
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Affiliation(s)
- Jie Zhang
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
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Krivenko AG, Kotkin AS, Kurmaz VA. Thermodynamic and kinetic characteristics of intermediates of electrode reactions: A comparative investigation of a number of alkylaryl and alkyl halide radicals by the laser photoemission methods. RUSS J ELECTROCHEM+ 2005. [DOI: 10.1007/s11175-005-0025-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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35
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Self-Assembly of Biomolecules on Electrode Surfaces; Oligonucleotides, Amino Acids, and Proteins toward the Single-Molecule Level. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/s1871-0069(05)01015-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
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36
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Electrochemical impedance spectroscopy study during accelerated life test of conductive oxides: Ti/(Ru + Ti + Ce)O2-system. Electrochim Acta 2004. [DOI: 10.1016/j.electacta.2004.05.043] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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37
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Koslowski T, Jurjiu A, Blumen A. Polaron Formation and Hopping Conduction in Hyperbranched Polymers: A Theoretical Approach. J Phys Chem B 2004. [DOI: 10.1021/jp037263a] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Thorsten Koslowski
- Institut für Physikalische Chemie II and Theoretische Polymerphysik, Universität Freiburg, D-79104 Freiburg im Breisgau, Germany
| | - Aurel Jurjiu
- Institut für Physikalische Chemie II and Theoretische Polymerphysik, Universität Freiburg, D-79104 Freiburg im Breisgau, Germany
| | - Alexander Blumen
- Institut für Physikalische Chemie II and Theoretische Polymerphysik, Universität Freiburg, D-79104 Freiburg im Breisgau, Germany
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Zhang J, Welinder AC, Hansen AG, Christensen HEM, Ulstrup J. Catalytic Monolayer Voltammetry and In Situ Scanning Tunneling Microscopy of Copper Nitrite Reductase on Cysteamine-Modified Au(111) Electrodes. J Phys Chem B 2003. [DOI: 10.1021/jp030923r] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jingdong Zhang
- Department of Chemistry, Building 207, Technical University of Denmark, DK-2800 Lyngby, Denmark
| | - Anne C. Welinder
- Department of Chemistry, Building 207, Technical University of Denmark, DK-2800 Lyngby, Denmark
| | - Allan G. Hansen
- Department of Chemistry, Building 207, Technical University of Denmark, DK-2800 Lyngby, Denmark
| | - Hans E. M. Christensen
- Department of Chemistry, Building 207, Technical University of Denmark, DK-2800 Lyngby, Denmark
| | - Jens Ulstrup
- Department of Chemistry, Building 207, Technical University of Denmark, DK-2800 Lyngby, Denmark
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Kennepohl P, Solomon EI. Electronic structure contributions to electron-transfer reactivity in iron-sulfur active sites: 1. Photoelectron spectroscopic determination of electronic relaxation. Inorg Chem 2003; 42:679-88. [PMID: 12562181 DOI: 10.1021/ic020330f] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Electronic relaxation, the change in molecular electronic structure as a response to oxidation, is investigated in [FeX(4)](2)(-)(,1)(-) (X = Cl, SR) model complexes. Photoelectron spectroscopy, in conjunction with density functional methods, is used to define and evaluate the core and valence electronic relaxation upon ionization of [FeX(4)](2)(-). The presence of intense yet formally forbidden charge-transfer satellite peaks in the PES data is a direct reflection of electronic relaxation. The phenomenon is evaluated as a function of charge redistribution at the metal center (Deltaq(rlx)) resulting from changes in the electronic structure. This charge redistribution is calculated from experimental core and valence PES data using a valence bond configuration interaction (VBCI) model. It is found that electronic relaxation is very large for both core (Fe 2p) and valence (Fe 3d) ionization processes and that it is greater in [Fe(SR)(4)](2)(-) than in [FeCl(4)](2)(-). Similar results are obtained from DFT calculations. The results suggest that, although the lowest-energy valence ionization (from the redox-active molecular orbital) is metal-based, electronic relaxation causes a dramatic redistribution of electron density ( approximately 0.7ē) from the ligands to the metal center corresponding to a generalized increase in covalency over all M-L bonds. The more covalent tetrathiolate achieves a larger Deltaq(rlx) because the LMCT states responsible for relaxation are significantly lower in energy than those in the tetrachloride. The large observed electronic relaxation can make significant contributions to the thermodynamics and kinetics of electron transfer in inorganic systems.
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Affiliation(s)
- Pierre Kennepohl
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA
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Kennepohl P, Solomon EI. Electronic structure contributions to electron-transfer reactivity in iron-sulfur active sites: 3. Kinetics of electron transfer. Inorg Chem 2003; 42:696-708. [PMID: 12562183 DOI: 10.1021/ic0203320] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The kinetics of electron transfer for rubredoxins are examined using density functional methods to determine the electronic structure characteristics that influence and allow for fast electron self-exchange in these electron-transport proteins. Potential energy surfaces for [FeX(4)](2-,1-) models confirm that the inner-sphere reorganization energy is inherently small for tetrathiolates ( approximately 0.1 eV), as evidenced by the only small changes in the equilibrium Fe-S bond distance during redox (Deltar(redox) approximately 0.05 A). It is concluded that electronic relaxation and covalency in the reduced state allow for this small in this case relative to other redox couples, such as the tetrachloride. Using a large computational model to include the protein medium surrounding the [Fe(SCys)(4)](2-,1-) active site in Desulfovibrio vulgaris Rubredoxin, the electronic coupling matrix element for electron self-exchange is defined for direct active-site contact (H0(DA)). Simple Beratan-Onuchic model is used to extend coupling over the complete surface of the protein to provide an understanding of probable electron-transfer pathways. Regions of similar coupling properties are grouped together to define a surface coupling map, which reveals that very efficient self-exchange occurs only within 4 sigma-bonds of the active site. Longer-range electron transfer cannot support the fast rates of electron self-exchange observed experimentally. Pathways directly through the two surface cysteinate ligands dominate, but surface-accessible amides hydrogen-bonded to the cysteinates also contribute significantly to the rate of electron self-exchange.
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Affiliation(s)
- Pierre Kennepohl
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA
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41
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Utz N, Koslowski T. Variational approach to charge transfer reactions in bridged triarylamine cations. Chem Phys 2002. [DOI: 10.1016/s0301-0104(02)00732-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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42
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Theoretical aspects of electron transfer reactions of complex molecules. Electrochim Acta 2001. [DOI: 10.1016/s0013-4686(01)00624-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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