Regularized Collocation in Distribution of Diffusion Times Applied to Electrochemical Impedance Spectroscopy

AbstractThis paper is inspired by recently proposed approach for interpreting data of Electrochemical Impedance Spectroscopy (EIS) in terms of Distribution of Diffusion Times (DDT). Such an interpretation requires to solve a Fredholm integral equation of the first kind, which may have a non-square-integrable kernel. We consider a class of equations with above-mentioned peculiarity and propose to regularize them in weighted functional spaces. One more issue associated with DDT-problem is that EIS data are available only for a finite number of frequencies. Therefore, a regularization should unavoidably be combined with a collocation. In this paper we analyze a regularized collocation in weighted spaces and propose a scheme for its numerical implementation. The performance of the proposed scheme is illustrated by numerical experiments with synthetic data mimicking EIS measurements.

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Verification of Redox Flow Batteries’ Functionality by Electrochemical Impedance Spectroscopy Tests

Batteries ◽

10.3390/batteries4040058 ◽

2018 ◽

Vol 4 (4) ◽

pp. 58 ◽

Cited By ~ 1

Author(s):

Daniel Manschke ◽

Thorsten Seipp ◽

Sascha Berthold ◽

K. Friedrich

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Electrochemical Impedance ◽

Comparison Method ◽

Redox Flow Batteries ◽

Current Voltage ◽

Flow Batteries ◽

Quantitative Statement ◽

Characteristic Values ◽

Eis Measurements

The state-of-the-art functionality test of classic redox-flow-stacks measures the current–voltage characteristic with the technical electrolyte. This research paper aims to simplify the validation of redox flow batteries’ functionality by conducting electrochemical impedance spectroscopy (EIS) on redox flow stacks. Since the electrolyte used in the batteries is usually toxic and aggressive, it would be a significant simplification to verify the functionality with an alternative, non-toxic fluid. EIS measurements on batteries with larger sized electrodes, multiple cells, and different fluids were performed. It was demonstrated that all impedances are repeatable, thereby validating this procedure as a qualification method for full-size and complex batteries with an alternative fluid. EIS measurements were able to detect deliberately manipulated cells. This research uses three different analysis methods for the acquired data to identify errors. The respective approaches are, firstly, (1) a comparison of the Nyquist plots; secondly, (2) a comparison of the Bode plots; and thirdly, (3) a comparison of the calculated characteristic values of the equivalent circuits. The analysis found that all methods are suitable to detect errors in the batteries. Nevertheless, the bode-plot comparison method proves to be especially advantageous, because it enables a quantitative statement.

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Impedimetric Characterization of Interdigitated Electrode Arrays for Biosensor Applications

Proceedings ◽

10.3390/proceedings2130899 ◽

2018 ◽

Vol 2 (13) ◽

pp. 899 ◽

Cited By ~ 3

Author(s):

Elisabeth Kostal ◽

Stephan Kasemann ◽

Can Dincer ◽

Stefan Partel

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Electrochemical Impedance ◽

Gap Size ◽

Electrode Arrays ◽

Electrode Gap ◽

Interdigitated Electrode ◽

Eis Measurements ◽

Biosensor Applications

We present recent results of the electrochemical impedance spectroscopy (EIS) measurements for interdigitated electrode arrays (IDAs) ranging from several micrometers down to hundreds of nanometers. Simulations have shown that the electric field strength between the electrodes scales with the gap size. Therefore, electrodes of varying gap sizes were fabricated and functionalized with ssDNA to empirically validate these findings. The results have shown that the impedimetric response strongly correlates with the width of the electrode fingers: the smaller the electrode gap, the larger the impedance increase.

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Detection of the Plant Pathogen Pseudomonas Syringae pv. Lachrymans on Antibody-Modified Gold Electrodes by Electrochemical Impedance Spectroscopy

Sensors ◽

10.3390/s19245411 ◽

2019 ◽

Vol 19 (24) ◽

pp. 5411 ◽

Cited By ~ 4

Author(s):

Zofia Cebula ◽

Sabina Żołędowska ◽

Karolina Dziąbowska ◽

Marta Skwarecka ◽

Natalia Malinowska ◽

...

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Pseudomonas Syringae ◽

Electrochemical Impedance ◽

Reference Method ◽

Sample Pretreatment ◽

Label Free ◽

Crop Species ◽

Eis Measurements ◽

Impedimetric Immunosensor

The present work describes an impedimetric immunosensor for Pseudomonas syringae pv. lachrymans (Psl) detection. This pathogen infects many crop species causing considerable yield losses, thus fast and cheap detection method is in high demand. In the assay, the gold disc electrode was modified with 4-aminothiophenol (4-ATP), glutaraldehyde (GA), and anti-Psl antibodies, and free-sites were blocked with bovine serum albumin (BSA). Sensor development was characterized by cyclic voltammetry (CV) and antigen detection by electrochemical impedance spectroscopy (EIS) measurements. Seven analyzed strains of Psl were verified as positive by the reference method (PCR) and this immunoassay, proving sensor specificity. Label-free electrochemical detection was in the linear range 1 × 103–1.2 × 105 CFU/mL (colony-forming unit) with an R2 coefficient of 0.992 and a detection limit (LOD) of 337 CFU/mL. The sensor did not interfere with negative probes like buffers and other bacteria. The assay was proven to be fast (10 min detection) and easy in preparation. The advantage was the simplicity and availability of the verified analyte (whole bacteria) as the method does not require sample pretreatment (e.g., DNA isolation). EIS biosensing technique was chosen as one of the simplest and most sensitive with the least destructive influence on the probes compared to other electrochemical methods.

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Electrochemical Impedance Spectroscopy (EIS) in Food, Water, and Drug Analyses: Recent Advances and Applications

Electrochemical Impedance Spectroscopy ◽

10.5772/intechopen.92333 ◽

2020 ◽

Author(s):

Marwa El-Azazy

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Electrochemical Impedance ◽

High Sensitivity ◽

Electrochemical Technique ◽

Water Safety ◽

Food Contaminants ◽

Sensitivity And Selectivity ◽

Ac Current ◽

Eis Measurements

Electrochemical impedance spectroscopy (EIS) is a potent electrochemical technique with a variety of applications. EIS measurements involve the application of an alternating current (AC) voltage (or current) to the system under investigation, followed by measurement of the response in the form of AC current (or voltage) as a function of frequency. By and large, EIS is an exceptionally attractive in terms of applications. Being nondestructive with a feasibility of implementation to the system to be measured and the usefulness of data obtained in characterizing the studied systems, electrochemical impedance spectroscopy has realms of applications. As food and water safety and security is becoming a universal concern, the need for a technique that can detect water and food contaminants with relatively high sensitivity and selectivity is evolving. EIS has started to realize its potential with a wide-term use in water and food analyses.

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A New Integrated Multi-Pathogen In Situ Detection Platform Using Electrochemical Impedance Spectroscopy

Proceedings ◽

10.3390/proceedings2131506 ◽

2018 ◽

Vol 2 (13) ◽

pp. 1506

Author(s):

Karlheinz Kellner ◽

Jörg Ettenauer ◽

Martin Brandl

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Pathogenic Bacteria ◽

Electrochemical Impedance ◽

Cell Model ◽

Successful Implementation ◽

Eis Measurements ◽

In Situ Detection ◽

Multiple Pathogens

Scientists are always searching for inventions and developing new methods for the detection of pathogenic bacteria in drinking water. Some of those techniques are based on electrochemical reactions, performed by a device called potentiostat. For in situ analysis, there is a high demand for hardware efficient instruments with a customized set of requirements including Electrochemical Impedance Spectroscopy (EIS) measurements. Therefore, we developed the ‘EcoStat’ device. As outcome of further developments, we demonstrate the successful implementation of an EIS feature and a multiplexing unit to achieve a detection platform for multiple pathogens. We present results performed on a simplified Randles Cell model.

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Rapid analytical instrumentation for electrochemical impedance spectroscopy measurements

10.1149/osf.io/w94xh ◽

2019 ◽

Author(s):

yuan hu ◽

Sean Brahim ◽

Stefan Maat ◽

Patricia Davies ◽

Arpan Kundu ◽

...

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Electrochemical Impedance ◽

Low Cost ◽

Wide Frequency Range ◽

Measurement Time ◽

Frequency Bands ◽

Commercial Instrument ◽

Adaptive Measurement ◽

Eis Measurements

This work reports a low-cost custom electrochemical instrument capable of performing rapid and accurate electrochemical impedance spectroscopy (EIS) for supercapacitors over a broad frequency band (10 mHz to 2 kHz). Conventionally, EIS is measured via sinusoidal perturbations; however, such an approach suffers from lengthy measurement time. Chirp signals have been shown previously to reduce EIS measurement time for supercapacitors for relative narrow frequency bands (1 Hz to 2 kHz). However, to characterize supercapacitors comprehensively, much broader frequency bands are required. Here, we present a custom instrument with an adaptive measurement algorithm for performing EIS measurements in a wide frequency range of 10 mHz to 2 kHz with low measurement uncertainties. The results obtained using this new technique has been validated here with a commercial instrument on several types of supercapacitors. Furthermore, measurement time on average decreases from 1500 s to less than 400 s. The overall cost of the custom instrument is 90% lower as compared to the commercial instrument. The custom instrument's accuracy, time efficiency and low cost are expected to benefit electrochemical researchers.

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Enrichment-Free Rapid Detection of Phthalates in Chinese Liquor with Electrochemical Impedance Spectroscopy

Sensors ◽

10.3390/s20030901 ◽

2020 ◽

Vol 20 (3) ◽

pp. 901

Author(s):

Xinyue Jiang ◽

Yuqun Xie ◽

Duanji Wan ◽

Fuping Zheng ◽

Jun Wang

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Metal Ion ◽

Electrochemical Impedance ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

Faradaic Impedance ◽

Chinese Liquor ◽

Non Invasive ◽

Eis Measurements

A non-invasive real-time detection technique for phthalates in Chinese liquor is proposed in this paper. This method is based on the measurement of Faradaic impedance in the presence of a redox probe, [Fe(CN)6]3−/4−, upon the absorption of phthalates to the graphene electrode surface. This absorption activity is according to the π–π stacking interactions between phthalates and the graphene working electrode which allows direct sampling and analyte preconcentration. The absorption of phthalates retards the interfacial electron-transfer kinetics and increases the charge-transfer resistance (Rct). Numerical values of Rct were extracted from a simulation of electrochemical impedance spectroscopy (EIS) spectra with the corresponding equivalent circuit. Cathodic polarization was employed prior to EIS measurements to effectively eliminate the metal ion interference. The results yielded a detection limit of 0.024 ng/L for diethyl phthalate (DEP) with a linear range from 2.22 ng to 1.11 µg. These results indicate a possibility of developing a household sensor for phthalate determination in Chinese liquor.

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Battery State Estimation for Lead-Acid Batteries under Float Charge Conditions by Impedance: Benchmark of Common Detection Methods

Applied Sciences ◽

10.3390/app8081308 ◽

2018 ◽

Vol 8 (8) ◽

pp. 1308 ◽

Cited By ~ 7

Author(s):

Julia Badeda ◽

Monika Kwiecien ◽

Dominik Schulte ◽

Dirk Sauer

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Electrochemical Impedance ◽

Relative Increase ◽

Detection Methods ◽

Uninterruptible Power Supply ◽

Lead Acid Batteries ◽

Uninterruptible Power ◽

Eis Measurements ◽

Lead Acid

Impedance or admittance measurements are a common indicator for the condition of lead-acid batteries in field applications such as uninterruptible power supply (UPS) systems. However, several commercially available measurement units use different techniques to measure and interpret the battery impedance. This paper describes common measurement methods and compares their indication for the state of health (SoH) to those of electrochemical impedance spectroscopy (EIS). For this analysis, two strings consisting each of 24 valve-regulated lead-acid (VRLA) batteries with a rated voltage of 12 V and about 7 Ah capacity were kept under standard UPS conditions in float charge for over 560 days. They were monitored continuously with a LEM Sentinel 2 and went into regular check-ups with impedance measurements by a Hioki BT3554 as well as electrochemical impedance spectroscopy (EIS) measurements with an impedance meter (μEIS). Today it is widely expected that solely the relative increase of the impedance reading is sufficient for the estimation of the available capacity. However, it can be shown that the measured relative increase deviates for different frequencies and therefore the choice of the excitation signal and measurement frequency does make a difference for the calculation of the available capacity. Finally, a method for a more decisive monitoring in field applications is suggested.

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Considerations on Reducing the Experimental Duration of Electrochemical Impedance Spectroscopy Measurements Used for the Evaluation of Ionic Conductivity in Polymer Electrolyte Membrane Electrolysers and Fuel Cells

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.415.61 ◽

2009 ◽

Vol 415 ◽

pp. 61-64 ◽

Cited By ~ 2

Author(s):

Danut Ionel Vaireanu ◽

Anca Cojocaru ◽

Ioana Maior ◽

Simona Caprarescu ◽

Alexandra Ionescu ◽

...

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Electrochemical Impedance ◽

Polymer Electrolyte Membrane ◽

Membrane Thickness ◽

Impedance Spectra ◽

Electrochemical Impedance Spectra ◽

Electrolyte Membrane ◽

Eis Measurements

In this paper one attempted to discuss the effect of reducing the experimental duration of electrochemical impedance spectroscopy (EIS) measurements by reducing the sampling frequency without affecting the measured parameters. The experimental setup is based on a novel cell consisting of two electrodes or three electrodes cell configuration. The experimental layout allows a precise evaluation of the membrane thickness, at micrometer resolution, during the determination of the electrochemical impedance spectra.

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ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY CHARACTERIZATION OF ZW3 MAGNESIUM ALLOY COATED BY DCPD USING LASV DEPOSITION TECHNIQUE

Acta Metallurgica Slovaca ◽

10.12776/ams.v23i2.900 ◽

2017 ◽

Vol 23 (2) ◽

pp. 147 ◽

Cited By ~ 4

Author(s):

Daniel Kajánek ◽

Branislav Hadzima ◽

Filip Pastorek ◽

Martina Neslušan Jacková

Keyword(s):

Electrochemical Impedance Spectroscopy ◽

Magnesium Alloy ◽

Impedance Spectroscopy ◽

Electrochemical Impedance ◽

Water Solution ◽

Electrochemical Characteristics ◽

Phosphate Dihydrate ◽

Nyquist Plots ◽

Eis Measurements

The contribution deals with the preparation of the dicalcium phosphate-dihydrate (DCPD) coating on ZW3 magnesium alloy surface. The coating was prepared using large amplitude sinusoidal voltammetry (LASV) electrodeposition technique in water solution of 0.1M Ca(NO3)2.4H2O + 0.06M NH4HPO4 + 10 ml.dm-3 of 50 vol.% H2O2. The influence of the DCPD coating on electrochemical characteristics was examined using potentiodynamic polarization (PD) tests and electrochemical impedance spectroscopy (EIS) at the temperature 22 ± 2 °C in 0.1M NaCl. The obtained PD curves were analysed using Tafel extrapolation method and the data obtained by EIS measurements in a form of Nyquist plots were analysed quantitatively by equivalent circuit method. The results showed the increase of corrosion resistance after application of DCPD coating on ZW3 Mg alloy in sodium chloride solution.

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