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Pinto MR, Costa GF, Machado EG, Nagao R. Self‐Organization in Electrochemical Synthesis as a Methodology towards New Materials. ChemElectroChem 2020. [DOI: 10.1002/celc.202000065] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Maria R. Pinto
- Institute of ChemistryUniversity of Campinas CEP 13083-970 Campinas, SP Brazil
| | - Gabriel F. Costa
- Institute of ChemistryUniversity of Campinas CEP 13083-970 Campinas, SP Brazil
| | - Eduardo G. Machado
- Institute of ChemistryUniversity of Campinas CEP 13083-970 Campinas, SP Brazil
- Center for Innovation on New EnergiesUniversity of Campinas CEP 13083-841 Campinas, SP Brazil
| | - Raphael Nagao
- Institute of ChemistryUniversity of Campinas CEP 13083-970 Campinas, SP Brazil
- Center for Innovation on New EnergiesUniversity of Campinas CEP 13083-841 Campinas, SP Brazil
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2
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Brau F, Haudin F, Thouvenel-Romans S, De Wit A, Steinbock O, Cardoso SSS, Cartwright JHE. Filament dynamics in confined chemical gardens and in filiform corrosion. Phys Chem Chem Phys 2018; 20:784-793. [DOI: 10.1039/c7cp06003c] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Once rescaled by the preferred wavenumber ω* of the curvature power spectrum, both filiform corrosion and chemical garden filaments display similar dynamics.
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Affiliation(s)
- Fabian Brau
- Université libre de Bruxelles (ULB)
- Nonlinear Physical Chemistry Unit
- Faculté des Sciences
- 1050 Brussels
- Belgium
| | - Florence Haudin
- Université libre de Bruxelles (ULB)
- Nonlinear Physical Chemistry Unit
- Faculté des Sciences
- 1050 Brussels
- Belgium
| | | | - Anne De Wit
- Université libre de Bruxelles (ULB)
- Nonlinear Physical Chemistry Unit
- Faculté des Sciences
- 1050 Brussels
- Belgium
| | - Oliver Steinbock
- Department of Chemistry and Biochemistry
- Florida State University
- Tallahassee
- USA
| | - Silvana S. S. Cardoso
- Department of Chemical Engineering and Biotechnology
- University of Cambridge
- Cambridge CB2 3RA
- UK
| | - Julyan H. E. Cartwright
- Instituto Andaluz de Ciencias de la Tierra
- CSIC-Universidad de Granada
- Granada
- Spain
- Instituto Carlos I de Física Teórica y Computacional
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3
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Inverse modeling of thin layer flow cells for detection of solubility, transport and reaction coefficients from experimental data. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2016.05.101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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4
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Bîrzu A, Jia Y, Sankuratri V, Liu Y, Kiss IZ. Spatially distributed current oscillations with electrochemical reactions in microfluidic flow cells. Chemphyschem 2015; 16:555-66. [PMID: 25598243 DOI: 10.1002/cphc.201402631] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Indexed: 01/19/2023]
Abstract
The formation of spatiotemporal patterns is investigated by using a chemical reaction on the surface of a high-aspect-ratio metal electrode positioned in a flow channel. A partial differential equation model is formulated for nickel dissolution in sulfuric acid in a microfluidic flow channel. The model simulations predict oscillatory patterns that are spatially distributed on the electrode surface; the downstream portion of the metal surface exhibits large-amplitude, nonlinear oscillations of dissolution rates, whereas the upstream portion displays small-amplitude, harmonic oscillations with a phase delay. The features of the dynamical response can be interpreted by the dependence of local dynamics on the widely varying surface conditions and the presence of strong coupling. The patterns can be observed for both contiguous and segmented metal surfaces. The existence of spatially distributed current oscillations is confirmed in experiments with Ni electrodissolution in a microfluidic device. The results show the impact of a widely heterogeneous environment on the types of patterns of chemical reaction rates.
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Affiliation(s)
- Adrian Bîrzu
- Department of Chemistry, Al. I. Cuza University, 11 Carol I Blvd., 700506 Iaşi (Romania); Department of Chemistry, Saint Louis University, 3501 Laclede Ave., St. Louis, MO 63103 (USA).
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6
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Nascimento MA, Nagao R, Eiswirth M, Varela H. Coupled slow and fast surface dynamics in an electrocatalytic oscillator: Model and simulations. J Chem Phys 2014; 141:234701. [DOI: 10.1063/1.4903172] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Melke A. Nascimento
- Institute of Chemistry of São Carlos, University of São Paulo, PO Box 780, 13560-970, São Carlos, SP, Brazil
- Fritz Haber Institute of the Max Planck Society, Department of Physical Chemistry, Faradayweg 4-6, D-14195 Berlin, Germany
| | - Raphael Nagao
- Institute of Chemistry of São Carlos, University of São Paulo, PO Box 780, 13560-970, São Carlos, SP, Brazil
| | - Markus Eiswirth
- Fritz Haber Institute of the Max Planck Society, Department of Physical Chemistry, Faradayweg 4-6, D-14195 Berlin, Germany
- Ertl Center for Electrochemistry and Catalysis, GIST, Cheomdan-gwagiro 261, Buk-gu, Gwangju 500-712, South Korea
| | - Hamilton Varela
- Institute of Chemistry of São Carlos, University of São Paulo, PO Box 780, 13560-970, São Carlos, SP, Brazil
- Fritz Haber Institute of the Max Planck Society, Department of Physical Chemistry, Faradayweg 4-6, D-14195 Berlin, Germany
- Ertl Center for Electrochemistry and Catalysis, GIST, Cheomdan-gwagiro 261, Buk-gu, Gwangju 500-712, South Korea
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7
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Bîrzu A, Coleman J, Kiss IZ. Highly disparate activity regions due to non-uniform potential distribution in microfluidic devices: Simulations and experiments. J Electroanal Chem (Lausanne) 2014. [DOI: 10.1016/j.jelechem.2014.05.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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8
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Siebert J, Alonso S, Bär M, Schöll E. Dynamics of reaction-diffusion patterns controlled by asymmetric nonlocal coupling as a limiting case of differential advection. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 89:052909. [PMID: 25353863 DOI: 10.1103/physreve.89.052909] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Indexed: 06/04/2023]
Abstract
A one-component bistable reaction-diffusion system with asymmetric nonlocal coupling is derived as a limiting case of a two-component activator-inhibitor reaction-diffusion model with differential advection. The effects of asymmetric nonlocal couplings in such a bistable reaction-diffusion system are then compared to the previously studied case of a system with symmetric nonlocal coupling. We carry out a linear stability analysis of the spatially homogeneous steady states of the model and numerical simulations of the model to show how the asymmetric nonlocal coupling controls and alters the steady states and the front dynamics in the system. In a second step, a third fast reaction-diffusion equation is included which induces the formation of more complex patterns. A linear stability analysis predicts traveling waves for asymmetric nonlocal coupling, in contrast to a stationary Turing patterns for a system with symmetric nonlocal coupling. These findings are verified by direct numerical integration of the full equations with nonlocal coupling.
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Affiliation(s)
- Julien Siebert
- Technische Universität, Institut für Theoretische Physik, Hardenberstrasse 36, 10623 Berlin, Germany
| | - Sergio Alonso
- Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, 10587 Berlin, Germany
| | - Markus Bär
- Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, 10587 Berlin, Germany
| | - Eckehard Schöll
- Technische Universität, Institut für Theoretische Physik, Hardenberstrasse 36, 10623 Berlin, Germany
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9
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Bulk concentration and dynamic stability of a model electrochemical system with a preceding chemical reaction. Electrochim Acta 2013. [DOI: 10.1016/j.electacta.2013.07.049] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Wickramasinghe M, Kiss IZ. Synchronization of electrochemical oscillators with differential coupling. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:062911. [PMID: 24483535 DOI: 10.1103/physreve.88.062911] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Indexed: 05/18/2023]
Abstract
Experiments are presented to describe the effect of capacitive coupling of two electrochemical oscillators during Ni dissolution in sulfuric acid solution. Equivalent circuit analysis shows that the coupling between the oscillators occurs through the difference between the differentials of the electrode potentials. The differential nature of the coupling introduces strong negative nonisochronicity (i.e., phase shear, strong dependence of the period on the amplitude) in the coupling mechanism with smooth oscillators (under conditions just above a Hopf bifurcation point). Because of the negative nonisochronicity, asymmetrically coupled oscillators exhibit anomalous phase synchronization in the form of frequency difference enhancement. At strong coupling bistability is observed between in-phase and antiphase synchronized states. With relaxation oscillators, in contrast to the resistive coupling where antiphase synchronization can occur, the typical system response with weak coupling is out-of-phase synchronization. When the capacitance is applied on the individual resistors attached to the electrodes the oscillators exhibit weak positive nonisochronicity; this is in contrast with the strong negative nonisochronicity obtained with cross coupling. The proposed coupling configurations reveal the importance of the nonisochronicity level of oscillations for the experimentally observed synchronization patterns and also provide efficient ways of tuning the nonisochronicity level of the oscillations. This latter feature can be exploited to design synchronization features with a combination of resistive (difference) and capacitive (differential) coupling.
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Affiliation(s)
- Mahesh Wickramasinghe
- Department of Chemistry, Saint Louis University, 3501 Laclede Avenue, St. Louis, Missouri 63103, USA
| | - István Z Kiss
- Department of Chemistry, Saint Louis University, 3501 Laclede Avenue, St. Louis, Missouri 63103, USA
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11
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Wu X, Ma J. The formation mechanism of defects, spiral wave in the network of neurons. PLoS One 2013; 8:e55403. [PMID: 23383179 PMCID: PMC3561244 DOI: 10.1371/journal.pone.0055403] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Accepted: 12/23/2012] [Indexed: 11/18/2022] Open
Abstract
A regular network of neurons is constructed by using the Morris-Lecar (ML) neuron with the ion channels being considered, and the potential mechnism of the formation of a spiral wave is investigated in detail. Several spiral waves are initiated by blocking the target wave with artificial defects and/or partial blocking (poisoning) in ion channels. Furthermore, possible conditions for spiral wave formation and the effect of partial channel blocking are discussed completely. Our results are summarized as follows. 1) The emergence of a target wave depends on the transmembrane currents with diversity, which mapped from the external forcing current and this kind of diversity is associated with spatial heterogeneity in the media. 2) Distinct spiral wave could be induced to occupy the network when the target wave is broken by partially blocking the ion channels of a fraction of neurons (local poisoned area), and these generated spiral waves are similar with the spiral waves induced by artificial defects. It is confirmed that partial channel blocking of some neurons in the network could play a similar role in breaking a target wave as do artificial defects; 3) Channel noise and additive Gaussian white noise are also considered, and it is confirmed that spiral waves are also induced in the network in the presence of noise. According to the results mentioned above, we conclude that appropriate poisoning in ion channels of neurons in the network acts as ‘defects’ on the evolution of the spatiotemporal pattern, and accounts for the emergence of a spiral wave in the network of neurons. These results could be helpful to understand the potential cause of the formation and development of spiral waves in the cortex of a neuronal system.
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Affiliation(s)
- Xinyi Wu
- Department of Physics, Lanzhou University of Technology, Lanzhou, China
| | - Jun Ma
- Department of Physics, Lanzhou University of Technology, Lanzhou, China
- * E-mail:
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12
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Das I, Goel N, Gupta SK, Agrawal NR. Electropolymerization of pyrrole: Dendrimers, nano-sized patterns and oscillations in potential in presence of aromatic and aliphatic surfactants. J Electroanal Chem (Lausanne) 2012. [DOI: 10.1016/j.jelechem.2012.01.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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13
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Kannan B, Williams DE, Khoshmanesh K, Bowmaker GA, Travas-Sejdic J. The electrochemical growth of conducting polymer “nanowires”. J Electroanal Chem (Lausanne) 2012. [DOI: 10.1016/j.jelechem.2012.01.022] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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14
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Mota A, Gonzalez ER, Eiswirth M. Kinetic insights over a PEMFC operating on stationary and oscillatory states. J Phys Chem A 2011; 115:13773-82. [PMID: 22017227 DOI: 10.1021/jp205341w] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Kinetic investigations in the oscillatory state have been carried out in order to shed light on the interplay between the complex kinetics exhibited by a proton exchange membrane fuel cell fed with poisoned H(2) (108 ppm of CO) and the other in serie process. The apparent activation energy (E(a)) in the stationary state was investigated in order to clarify the E(a) observed in the oscillatory state. The apparent activation energy in the stationary state, under potentiostatic control, rendered (a) E(a) ≈ 50-60 kJ mol(-1) over 0.8 V < E < 0.6 V and (b) E(a) ≈ 10 kJ mol(-1) at E = 0.3 V. The former is related to the H(2) adsorption in the vacancies of the surface poisoned by CO and the latter is correlated to the process of proton conductivity in the membrane. The dependence of the period-one oscillations on the temperature yielded a genuine Arrhenius dependence with two E(a) values: (a) E(a) around 70 kJ mol(-1), at high temperatures, and (b) E(a) around 10-15 kJ mol(-1), at lower temperatures. The latter E(a) indicates the presence of protonic mass transport coupled to the essential oscillatory mechanism. These insights point in the right direction to predict spatial couplings between anode and cathode as having the highest strength as well as to speculate the most likely candidates to promote spatial inhomogeneities.
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Affiliation(s)
- Andressa Mota
- Instituto de Química de São Carlos, Av. Trab. Sancarlense 400, CEP 13560-970, São Carlos-SP, Brazil.
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15
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Das I, Choudhary R, Gupta SK, Agrawal P. Nanostructured Growth Patterns and Chaotic Oscillations in Potential during Electropolymerization of Aniline in the Presence of Surfactants. J Phys Chem B 2011; 115:8724-31. [DOI: 10.1021/jp1095757] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ishwar Das
- Chemistry Department, DDU Gorakhpur University, Gorakhpur-273009, India
| | | | | | - Pranav Agrawal
- Department of Chemical Engineering, Indian Institute of Technology, Kanpur-208016, India
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16
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Sadeghi S, Thompson M. Towards information processing from nonlinear physical chemistry: A synthetic electrochemical cognitive system. Biosystems 2010; 102:99-111. [DOI: 10.1016/j.biosystems.2010.08.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Accepted: 08/02/2010] [Indexed: 10/19/2022]
Affiliation(s)
- Saman Sadeghi
- Crump Institute for Molecular Imaging, UCLA, 570 Westwood Plaza, Building 114, Los Angeles, CA 90095, USA.
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18
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Sadeghi S, Thompson M. Temporal patterns and oscillatory voltage perturbation during an electrochemical process. Phys Chem Chem Phys 2010; 12:6795-809. [DOI: 10.1039/c000966k] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Sitta E, Nascimento MA, Varela H. Complex kinetics, high frequency oscillations and temperature compensation in the electro-oxidation of ethylene glycol on platinum. Phys Chem Chem Phys 2010; 12:15195-206. [PMID: 20661518 DOI: 10.1039/c002574g] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Elton Sitta
- Instituto de Química de São Carlos, Universidade de São Paulo C.P. 780, CEP 13560-970, São Carlos, SP, Brazil
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20
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Kiss IZ, Munjal N, Martin RS. Synchronized Current Oscillations of Formic Acid Electro-oxidation in a Microchip-based Dual-Electrode Flow Cell. Electrochim Acta 2009; 55:395-403. [PMID: 20160883 PMCID: PMC2772206 DOI: 10.1016/j.electacta.2009.02.094] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We investigate the oscillatory electro-oxidation of formic acid on platinum in a microchip-based dual-electrode cell with microfluidic flow control. The main dynamical features of current oscillations on single Pt electrode that had been observed in macro-cells are reproduced in the microfabricated electrochemical cell. In dual-electrode configuration nearly in-phase synchronized current oscillations occur when the reference/counter electrodes are placed far away from the microelectrodes. The synchronization disappears with close reference/counter electrode placements. We show that the cause for synchronization is weak albeit important, bidirectional electrical coupling between the electrodes; therefore the unidirectional mass transfer interactions are negligible. The experimental design enables the investigation of the dynamical behavior in micro-electrode arrays with well-defined control of flow of the electrolyte in a manner where the size and spacing of the electrodes can be easily varied.
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Affiliation(s)
- István Z. Kiss
- Saint Louis University, Department of Chemistry, 3501 Laclede Ave., St. Louis, MO 63103
| | - Neil Munjal
- Saint Louis University, Department of Chemistry, 3501 Laclede Ave., St. Louis, MO 63103
| | - R. Scott Martin
- Saint Louis University, Department of Chemistry, 3501 Laclede Ave., St. Louis, MO 63103
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21
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Interfacial energy gradient at a front of an electrochemical wave appearing in CuSn-alloy oscillatory electrodeposition. Electrochim Acta 2009. [DOI: 10.1016/j.electacta.2009.02.034] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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22
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The effect of IR compensation on stationary and oscillatory patterns in dual-electrode metal dissolution systems. Electrochim Acta 2009. [DOI: 10.1016/j.electacta.2009.02.105] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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23
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Birzu A, Krischer K. Confined Spatio-Temporal Chaos During Metal Electrodissolution: Simulations. Z PHYS CHEM 2009. [DOI: 10.1524/zpch.2007.221.9-10.1245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The electrodissolution of metal electrodes exhibits often sustained oscillations of the current density. We study the spatio-temporal dynamics of a metal disk electrode embedded in an insulator in a cylindrical electrochemical cell with a ring-shaped CE in the oscillatory region. The chosen cell geometry introduces a strong radial parameter dependence into the system. For low conductivity the dynamics is spatio-temporally chaotic. A small aspect ratio of the cell supports 2-dimensional space-time chaos on the entire disk electrode. For larger aspect ratios and thus larger parameter gradients, however, we observe a ‘self-confinement’ of the turbulent dynamics to the central part of the disk electrode, the outer ring of the electrode exhibiting angularly uniform oscillations. It can be expected that the state of confined chaos is not restricted to electrochemical systems but can be established also in other dynamical systems by introducing an appropriate parameter gradient.
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Karantonis A, Koutsaftis D, Kouloumbi N. Synchronization properties of coupled electrochemical bursters. J APPL ELECTROCHEM 2009. [DOI: 10.1007/s10800-009-9926-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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25
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Jiang F, Munkholm A, Wang RV, Streiffer SK, Thompson C, Fuoss PH, Latifi K, Elder KR, Stephenson GB. Spontaneous oscillations and waves during chemical vapor deposition of InN. PHYSICAL REVIEW LETTERS 2008; 101:086102. [PMID: 18764640 DOI: 10.1103/physrevlett.101.086102] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2008] [Indexed: 05/26/2023]
Abstract
We report observations of self-sustaining spatiotemporal chemical oscillations during metal-organic chemical vapor deposition of InN onto GaN. Under constant supply of vapor precursors trimethylindium and NH3, the condensed-phase cycles between crystalline islands of InN and elemental In droplets. Propagating fronts between regions of InN and In occur with linear, circular, and spiral geometries. The results are described by a model in which the nitrogen activity produced by surface-catalyzed NH3 decomposition varies with the exposed surface areas of GaN, InN, and In.
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Affiliation(s)
- F Jiang
- Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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Nakanishi S, Nagai T, Fukami K, Sonoda K, Oka N, Ihara D, Nakato Y. Oscillatory electrodeposition of metal films at liquid/liquid interfaces induced by the large surface energy of growing deposits. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:2564-2568. [PMID: 18247477 DOI: 10.1021/la7033565] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Electrodeposition of zinc (Zn) at an aqueous ZnSO4/n-butylacetate (BuAc) interface (liquid/liquid (LL) interface) showed a potential oscillation in the region of the current density exceeding the diffusion-limited one, accompanied by formation of two-dimensional Zn film with a concentric pattern at the LL interface. In-situ optical microscopic inspections revealed that the oscillatory growth of the Zn film synchronized with meniscus oscillation of the LL interface. The vigorous growth of the deposits occurs only when the shape of the meniscus becomes hollow on the negative potential side of the potential oscillation. On the other hand, on the positive side, the meniscus becomes almost flat and the deposits formed in the preceding stage are thickened. A mechanism is proposed to explain the oscillatory Zn electrodeposition coupled with the meniscus oscillation, on the basis of the fact that the interfacial tension at the growing metal/aqueous solution interface is extremely large.
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Affiliation(s)
- Shuji Nakanishi
- Division of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
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Baba N, Krischer K. Mixed-mode oscillations and cluster patterns in an electrochemical relaxation oscillator under galvanostatic control. CHAOS (WOODBURY, N.Y.) 2008; 18:015103. [PMID: 18377084 DOI: 10.1063/1.2779856] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We studied the dynamics of a prototypical electrochemical model, the electro-oxidation of hydrogen in the presence of poisons, under galvanostatic conditions. The lumped system exhibits relaxation oscillations, which develop mixed-mode oscillations (MMOs) for low preset currents. A fast-slow analysis of the homogeneous dynamics reveals that the MMOs arise from a fast oscillating subsystem and a one-dimensional slow manifold. In the spatially extended system, the galvanostatic constraint imposes a synchronizing global coupling that drives the system into cluster patterns. The properties of the cluster patterns (CPs) result from an intricate interplay of the nature of the local oscillators, the global constraint, and a nonlocal coupling through the electrolyte. In particular, we find that the global constraint suppresses small-amplitude oscillations of MMOs and prevents domains oscillating out of phase from occupying equal regions in phase space. The nonlocal coupling causes each individual clustered region to oscillate on a different limit cycle. Typically multistability of CPs is found. Coexisting patterns possess different oscillation periods and a different total fraction in space that occupies the in-phase or out-of-phase state, respectively.
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Affiliation(s)
- Nilüfer Baba
- Physik Department E19, Technische Universität München, James Franck Strasse 1, 85748 Garching bei München, Germany
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28
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Bifurcation analysis of bistability between spatially uniform and non-uniform electrochemical oscillations. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2007.12.077] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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29
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Fukushima S, Nakanishi S, Nakato Y, Ogawa T. Selection principle for various modes of spatially nonuniform electrochemical oscillations. J Chem Phys 2008; 128:014714. [DOI: 10.1063/1.2799994] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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30
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The external-pulse introduced pattern in a system with a closer reference electrode and a quasi-one-dimensional ribbon working electrode. Electrochim Acta 2007. [DOI: 10.1016/j.electacta.2007.07.011] [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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31
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Lee J, Christoph J, Noh T, Eiswirth M, Ertl G. Edge effects in an electrochemical reaction: HCOOH oxidation on a Pt ribbon. J Chem Phys 2007; 126:144702. [PMID: 17444727 DOI: 10.1063/1.2717163] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The use of a ribbon-shaped Pt electrode gives rise to edge effects of the interfacial potential, as is predicted from the potential theory in the form of the corresponding reaction-migration equation. They are studied in the bistable region of formic acid oxidation. Essentially, the edges tend to be more passive than the bulk of the electrode, which also causes a passivation (activation) transition to originate from the edges (center) of the ribbon. The experimental results are in agreement with simulations of the reaction-migration system.
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Affiliation(s)
- Jaeyoung Lee
- Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712, South Korea
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Bîrzu A, Krischer K. Two-dimensional electrochemical turbulence during the electrodissolution of metal disk electrodes: Model calculations. Phys Chem Chem Phys 2006; 8:3659-68. [PMID: 16883395 DOI: 10.1039/b606985a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present numerical studies of the spatio-temporal dynamics of disk electrodes with local limit cycle oscillations. The simulations are done with a realistic 3-D geometry of the electrochemical cell and disk-shaped working electrodes (WE). Spatio-temporal chaos is shown to exist from a critical electrode size onwards. It is analyzed by Karhunen-Loève decomposition and Hilbert transform. The former shows that the chaos becomes more complex with increasing system size, the latter allows features that generate the spatio-temporal complexity to be identified, namely, spatially extended 1-D phase defects and topological defects.
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Affiliation(s)
- Adrian Bîrzu
- Technische Universität München, Physik Department E19, James Franck Strasse 1, D-85748, Garching, Germany
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Bordyugov G, Engel H. Creating bound states in excitable media by means of nonlocal coupling. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2006; 74:016205. [PMID: 16907175 DOI: 10.1103/physreve.74.016205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2006] [Revised: 05/11/2006] [Indexed: 05/11/2023]
Abstract
We consider pulses of excitation in reaction-diffusion systems subjected to nonlocal coupling. This coupling represents long-range connections between the elements of the medium; the connection strength decays exponentially with the distance. Without coupling, pulses interact only repulsively and bound states with two or more pulses propagating at the same velocity are impossible. Upon switching on nonlocal coupling, pulses begin to interact attractively and form bound states. First we present numerical results on the emergence of bound states in the excitable Oregonator model for the photosensitive Belousov-Zhabotinsky reaction with nonlocal coupling. Then we show that the appearance of bound states is provided solely by the exponential decay of nonlocal coupling and thus can be found in a wide class of excitable systems, regardless of the particular kinetics. The theoretical explanation of the emergence of bound states is based on the bifurcation analysis of the profile equations that describe the spatial shape of pulses. The central object is a codimension-4 homoclinic orbit which exists for zero coupling strength. The emergence of bound states is described by the bifurcation to 2-homoclinic solutions from the codimension-4 homoclinic orbit upon switching on nonlocal coupling. We stress that the high codimension of the bifurcation to bound states is generic, provided that the coupling range is sufficiently large.
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Affiliation(s)
- Grigory Bordyugov
- Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergerstrasse 36, 10623 Berlin, Germany.
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Plenge F, Varela H, Krischer K. Pattern formation in stiff oscillatory media with nonlocal coupling: a numerical study of the hydrogen oxidation reaction on Pt electrodes in the presence of poisons. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 72:066211. [PMID: 16486044 DOI: 10.1103/physreve.72.066211] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2005] [Indexed: 05/06/2023]
Abstract
The impact of the strength of negative (desynchronizing) global coupling (NGC) on the spatiotemporal dynamics of an electrochemical relaxation oscillator is studied numerically with a prototypical model, the electro-oxidation of hydrogen in the presence of poisons. The results are compared with recent experiments. The NGC has a destabilizing effect on the homogeneous oscillations. Both, in theory and in experiments, the basic patterns found with increasing global coupling strength are modulated oscillations, target patterns (including an asymmetric variant), and modulated pulses, the average spatial inhomogeneity during an oscillation increasing with the intensity of the NGC. It is suggested that this scenario is typical for strong relaxation oscillations, and a comparison with an electrochemical oscillator exhibiting harmonic oscillations points to the fact that the critical coupling strength, upon which the complete synchronization is destroyed, is larger for relaxation oscillations than for harmonic oscillations. In addition, the numerical simulations predicted two- and three-phase cluster patterns at high coupling strength. Also in experiments cluster patterns were observed, however only in parameter regions of the local dynamics which were different from the one investigated in this study.
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Affiliation(s)
- F Plenge
- Fritz-Haber Institute of the Max-Planck Society, Faradayweg 4-6, 14195 Berlin, Germany
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Nakanishi S, Sakai SI, Nagai T, Nakato Y. Macroscopically Uniform Nanoperiod Alloy Multilayers Formed by Coupling of Electrodeposition with Current Oscillations. J Phys Chem B 2005; 109:1750-5. [PMID: 16851154 DOI: 10.1021/jp045876x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The electrodeposition from an acidic solution containing Cu(2+), Sn(2+), and a cationic surfactant gave a negative differential resistance (NDR) and a current oscillation in a narrow potential region of about 20 mV lying slightly more negative than the onset potential for Sn-Cu alloy deposition. Scanning Auger microscopic inspection has indicated that alloy films deposited during the oscillation have a clear alternate multilayer structure composed of two alloy layers of different compositions. The multilayer had the period of thickness of 40-90 nm and was uniform over a macroscopically wide area of about 1 mm x 1 mm. Detailed investigations have revealed that the NDR arises from adsorption of a cationic surfactant (acting as an inhibitor for diffusion of metal ions) on the alloy surface, and the oscillation comes from coupling of the NDR with the ohmic drop in the electrolyte.
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Affiliation(s)
- Shuji Nakanishi
- Division of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
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Nakanishi S, Fukami K, Tada T, Nakato Y. Metal Latticeworks Formed by Self-Organization in Oscillatory Electrodeposition. J Am Chem Soc 2004; 126:9556-7. [PMID: 15291556 DOI: 10.1021/ja047042y] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Strikingly well-ordered Sn latticeworks, standing perpendicular to the substrate, are formed spontaneously in oscillatory electrodeposition. Cooperation of various processes, such as needle formation by autocatalytic crystal growth, cuboid formation under a reaction-limited condition, and autocatalytic oxidation at closest-packed surfaces, enabled the self-organization of the latticeworks. The mechanism is generally applicable to deposition of other metals such as Zn, Pb, and Cu. The present work has opened a promising, unique field toward the formation of highly ordered 3-D micro- or nanostructures at solid surfaces.
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Affiliation(s)
- Shuji Nakanishi
- Division of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
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Plenge F, Li YJ, Krischer K. Spatial Bifurcations in the Generic N−NDR Electrochemical Oscillator with Negative Global Coupling: Theory and Surface Plasmon Experiments. J Phys Chem B 2004. [DOI: 10.1021/jp037955z] [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)
- F. Plenge
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany, and Physik Department, Technische Universität München, James-Franck-Strasse 1, 85748 Garching, Germany
| | - Y.-J. Li
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany, and Physik Department, Technische Universität München, James-Franck-Strasse 1, 85748 Garching, Germany
| | - K. Krischer
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany, and Physik Department, Technische Universität München, James-Franck-Strasse 1, 85748 Garching, Germany
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Karantonis A, Pagitsas M, Miyakita Y, Nakabayashi S. In-Phase, Anti-Phase and Fractured Synchrony in Ring Networks of Coupled Relaxation Electrochemical Oscillators. J Phys Chem B 2004. [DOI: 10.1021/jp049767u] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- A. Karantonis
- Department of Materials Science and Engineering, School of Chemical Engineering, National Technical University of Athens, Zografou 15780, Athens, Greece, Department of Chemistry, Faculty of Science, Aristotle University of Thessaloniki, Thessaloniki 54006, Greece, and Department of Chemistry, Faculty of Science, Saitama University, Saitama 338-8570, Japan
| | - M. Pagitsas
- Department of Materials Science and Engineering, School of Chemical Engineering, National Technical University of Athens, Zografou 15780, Athens, Greece, Department of Chemistry, Faculty of Science, Aristotle University of Thessaloniki, Thessaloniki 54006, Greece, and Department of Chemistry, Faculty of Science, Saitama University, Saitama 338-8570, Japan
| | - Y. Miyakita
- Department of Materials Science and Engineering, School of Chemical Engineering, National Technical University of Athens, Zografou 15780, Athens, Greece, Department of Chemistry, Faculty of Science, Aristotle University of Thessaloniki, Thessaloniki 54006, Greece, and Department of Chemistry, Faculty of Science, Saitama University, Saitama 338-8570, Japan
| | - S. Nakabayashi
- Department of Materials Science and Engineering, School of Chemical Engineering, National Technical University of Athens, Zografou 15780, Athens, Greece, Department of Chemistry, Faculty of Science, Aristotle University of Thessaloniki, Thessaloniki 54006, Greece, and Department of Chemistry, Faculty of Science, Saitama University, Saitama 338-8570, Japan
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Varela H, Bonnefont A, Krischer K. Trapping Electrochemical Oscillations between Self-Organized Potential Walls. Chemphyschem 2003; 4:1348-51. [PMID: 14714385 DOI: 10.1002/cphc.200300922] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Hamilton Varela
- Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6, 14195 Berlin, Germany
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Bîrzu A, Plenge F, Jaeger NI, Hudson JL, Krischer K. Complex Spatiotemporal Antiphase Oscillations during Electrodissolution of a Metal Disk Electrode: Model Calculations. J Phys Chem B 2003. [DOI: 10.1021/jp022457w] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Adrian Bîrzu
- Department of Physics, Technical University of München, James-Franck-Strasse 1, 85748 Garching, Germany, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin, Germany, Institute for Applied and Physical Chemistry, University of Bremen, FB 2-Biology/Chemistry, Postfach 330 440, 28334 Bremen, Germany, and Department of Chemical Engineering, 102 Engineers' Way, University of Virginia, Charlottesville, Virginia 22904-4741
| | - Florian Plenge
- Department of Physics, Technical University of München, James-Franck-Strasse 1, 85748 Garching, Germany, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin, Germany, Institute for Applied and Physical Chemistry, University of Bremen, FB 2-Biology/Chemistry, Postfach 330 440, 28334 Bremen, Germany, and Department of Chemical Engineering, 102 Engineers' Way, University of Virginia, Charlottesville, Virginia 22904-4741
| | - Nils I. Jaeger
- Department of Physics, Technical University of München, James-Franck-Strasse 1, 85748 Garching, Germany, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin, Germany, Institute for Applied and Physical Chemistry, University of Bremen, FB 2-Biology/Chemistry, Postfach 330 440, 28334 Bremen, Germany, and Department of Chemical Engineering, 102 Engineers' Way, University of Virginia, Charlottesville, Virginia 22904-4741
| | - John L. Hudson
- Department of Physics, Technical University of München, James-Franck-Strasse 1, 85748 Garching, Germany, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin, Germany, Institute for Applied and Physical Chemistry, University of Bremen, FB 2-Biology/Chemistry, Postfach 330 440, 28334 Bremen, Germany, and Department of Chemical Engineering, 102 Engineers' Way, University of Virginia, Charlottesville, Virginia 22904-4741
| | - Katharina Krischer
- Department of Physics, Technical University of München, James-Franck-Strasse 1, 85748 Garching, Germany, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, 14195 Berlin, Germany, Institute for Applied and Physical Chemistry, University of Bremen, FB 2-Biology/Chemistry, Postfach 330 440, 28334 Bremen, Germany, and Department of Chemical Engineering, 102 Engineers' Way, University of Virginia, Charlottesville, Virginia 22904-4741
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Bîrzu A, Plenge F, Jaeger NI, Hudson JL, Krischer K. Excitable dynamics during electrodissolution of a metal disk electrode: model calculations. Phys Chem Chem Phys 2003. [DOI: 10.1039/b303222a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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