Experimental Strategy for Characterization of Essential Dynamical Variables in Oscillatory Systems:  Effect of Double-Layer Capacitance on the Stability of Electrochemical Oscillators

Kiss, István Z.; Kazsu, Zoltán; Gáspár, Vilmos

doi:10.1021/jp053656t

Cited by 14 publications

(10 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The overall dynamical features are thus consistent with those observed with large (e.g., 1 and 2 mm diameter) electrodes in traditional macrocells. [2, 6, 24, 25, 34-36]…”

Section: Discussionmentioning

confidence: 99%

Electrochemical oscillations of nickel electrodissolution in an epoxy-based microchip flow cell

Cioffi

Martin

Kiss

2011

Journal of Electroanalytical Chemistry

Self Cite

View full text Add to dashboard Cite

We investigate the nonlinear dynamics of transpassive electrodissolution of nickel in sulfuric acid in an epoxy-based microchip flow cell. We observed bistability, smooth, relaxation, and period-2 waveform current oscillations with external resistance attached to the electrode in the microfabricated electrochemical cell with 0.05 mm diameter Ni wire under potentiostatic control. Experiments with 1mm × 0.1 mm Ni electrode show spontaneous oscillations without attached external resistance; similar surface area electrode in macrocell does not exhibit spontaneous oscillations. Combined experimental and numerical studies show that spontaneous oscillation with the on-chip fabricated electrochemical cell occurs because of the unusually large ohmic potential drop due to the constrained current in the narrow flow channel. This large IR potential drop is expected to have an important role in destabilizing negative differential resistance electrochemical (e.g., metal dissolution and electrocatalytic) systems in on-chip integrated microfludic flow cells. The proposed experimental setup can be extendend to multi-electrode configurations; the epoxy-based substrate procedure thus holds promise in electroanalytical applications that require collector-generator multi-electrodes wires with various electrode sizes, compositions, and spacings as well as controlled flow conditions.

show abstract

“…The overall dynamical features are thus consistent with those observed with large (e.g., 1 and 2 mm diameter) electrodes in traditional macrocells. [2, 6, 24, 25, 34-36]…”

Section: Discussionmentioning

confidence: 99%

Electrochemical oscillations of nickel electrodissolution in an epoxy-based microchip flow cell

Cioffi

Martin

Kiss

2011

Journal of Electroanalytical Chemistry

Self Cite

View full text Add to dashboard Cite

show abstract

“…The reaction of those molecules can thus be thought as one of the simplest yet very interesting experimental systems. Of late, Kiss and co-workers [21]–[22], [23], [24] have discussed the role of temperature and some electrical properties on the oscillation features. For a NDR oscillator, which typically oscillates under potentiostatic control, the authors found theoretically and experimentally that the frequency of oscillations is directly related to the square root of the velocity of charge transfer [21].…”

Section: Introductionmentioning

confidence: 99%

Experimental Assessment of the Sensitiveness of an Electrochemical Oscillator towards Chemical Perturbations

2012

View full text Add to dashboard Cite

In this study we address the problem of the response of a (electro)chemical oscillator towards chemical perturbations of different magnitudes. The chemical perturbation was achieved by addition of distinct amounts of trifluoromethanesulfonate (TFMSA), a rather stable and non-specifically adsorbing anion, and the system under investigation was the methanol electro-oxidation reaction under both stationary and oscillatory regimes. Increasing the anion concentration resulted in a decrease in the reaction rates of methanol oxidation and a general decrease in the parameter window where oscillations occurred. Furthermore, the addition of TFMSA was found to decrease the induction period and the total duration of oscillations. The mechanism underlying these observations was derived mathematically and revealed that inhibition in the methanol oxidation through blockage of active sites was found to further accelerate the intrinsic non-stationarity of the unperturbed system. Altogether, the presented results are among the few concerning the experimental assessment of the sensitiveness of an oscillator towards chemical perturbations. The universal nature of the complex chemical oscillator investigated here might be used for reference when studying the dynamics of other less accessible perturbed networks of (bio)chemical reactions.

show abstract

“…Some of these suggestions will be given later in this book, in the discussion of selected experimental oscillatory systems. Here we shall mention that Kiss et al [50] have suggested the application of the method of changing the time scale associated with dynamical variables (see Sect. 2.3) to the classification of the fact that recursive feedback controller can be applied to add (positive or negative) pseudocapacitance to the inherent double layer capacitance of the electrochemical system.…”

Section: Classification Of Electrochemical Oscillators Based On Impedmentioning

confidence: 99%

“…An analogous approach is potentially applicable to CSTR systems, where the inlet concentrations of chemicals could be changed proportional to the concurrently determined time derivative of concentrations [50]. In this way also chemical species essential for the oscillations could be explicitly detected.…”

Section: Classification Of Electrochemical Oscillators Based On Impedmentioning

confidence: 99%

Application of Impedance Spectroscopy to Electrochemical Instabilities

Orlik

2012

Monographs in Electrochemistry

View full text Add to dashboard Cite

Electrochemical impedance spectroscopy (EIS), a well-established technique in classical electrochemistry [1], can also be very useful for the analysis of stability of electrochemical systems, including diagnosis of selected bifurcations. Impedance spectra of such dynamical systems allow also classify electrochemical oscillators into respective types. In fact, due to linearization involved in the concept of impedance, this way of the stability analysis of electric (electrochemical) circuits is a specific variant of linear stability analysis described in Sect. 1.3.In this section a short presentation of the principle of impedance measurements is described, in order to make the reader familiar with the notation used further in this chapter. The basis for this summary will be typical (Randles-type) equivalent circuit from Fig. 2.6, in which Z f will henceforth mean generally the ac impedance, measured for ac frequency f [Hz] (or angular frequency o ¼ 2pf [rad s À1 ]). The idea of such equivalent circuits, coming from the seminal work of Randles [2], was concordant with the experimental equipment used in early times of impedance measurements. It involved the ac bridge, in which one branch contained the experimental system, the impedance characteristics of which had to be balanced, in the other branch, by the impedance of the electric (equivalent) circuit, possibly closely reflecting the properties of the experimental one.Typically the electrochemical cell is first brought into steady-state, or at least quasi-steady-state (E ss , I ss ) which is further perturbed with the externally applied small amplitude, sinusoidal ac voltage (typically) or ac current. As a consequence, the electrode potential E and the current I will oscillate around their steady-state values with the same frequency o, but in general case exhibiting (frequency dependent) phase difference. In general notation one can denote the phase shifts for both the electrode potential and the current as ' 1 and ' 2 , respectively, and then:M. Orlik, Self-Organization in Electrochemical Systems I, Monographs in Electrochemistry,

show abstract

Experimental Strategy for Characterization of Essential Dynamical Variables in Oscillatory Systems: Effect of Double-Layer Capacitance on the Stability of Electrochemical Oscillators

Cited by 14 publications

References 47 publications

Electrochemical oscillations of nickel electrodissolution in an epoxy-based microchip flow cell

Electrochemical oscillations of nickel electrodissolution in an epoxy-based microchip flow cell

Experimental Assessment of the Sensitiveness of an Electrochemical Oscillator towards Chemical Perturbations

Application of Impedance Spectroscopy to Electrochemical Instabilities

Contact Info

Product

Resources

About