Potassium-Selective Solid-Contact Electrode with High-Capacitance Hydrous Iridium Dioxide in the Transduction Layer

This work presents new material for solid-contact layers—hydrous iridium dioxide IrO2·2H2O, characterized by high electrical capacitance value, evaluated using chronopotentiometry (1.22 mF) and electrochemical impedance spectroscopy (1.57 mF). The remarkable electrical parameters of layers resulted in great analytical parameters of IrO2·2H2O-contacted potassium-selective electrodes. Various parameters of ion-selective electrodes were examined in the scope of this work using a potentiometry method including: linear range, repeatability, stability of potentiometric response and sensitivity to varying measurement conditions. The analytical parameters obtained for solid-contact electrodes were compared with the ones obtained for coated disc electrodes to evaluate the influence of the iridium dioxide layer. The linear range of the IrO2·2H2O-contacted K+-selective electrodes covered concentrations of K+ ions from 10−6 to 10−1 M and the potential stability was estimated at 0.097 mV/h. The IrO2·2H2O-contacted electrodes turned out to be insensitive to varying light exposure and changes in the pH values of measured solutions (in the pH range of 2 to 10.5). A water layer test proved that, contrary to the coated disc electrode, the substantial water film is not formed between the ion-selective membrane and iridium dioxide layer.

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Potentiometric Carboxylate Sensors Based on Carbazole-Derived Acyclic and Macrocyclic Ionophores

Chemosensors ◽

10.3390/chemosensors9010004 ◽

2020 ◽

Vol 9 (1) ◽

pp. 4

Author(s):

Ville Yrjänä ◽

Indrek Saar ◽

Mihkel Ilisson ◽

Sandip A. Kadam ◽

Ivo Leito ◽

...

Keyword(s):

Detection Limit ◽

Vinyl Chloride ◽

Anion Exchanger ◽

Linear Range ◽

Ph Sensitivity ◽

Ion Selective Electrodes ◽

Solid Contact ◽

Response Characteristics ◽

Potentiometric Response ◽

Poly Vinyl Chloride

Solid-contact ion-selective electrodes with carbazole-derived ionophores were prepared. They were characterized as acetate sensors, but can be used to determine a number of carboxylates. The potentiometric response characteristics (slope, detection limit, selectivity, and pH sensitivity) of sensors prepared with different membrane compositions (ionophore, ionophore concentration, anion exchanger concentration, and plasticizer) were evaluated. The results show that for the macrocyclic ionophores, a larger cavity provided better selectivity. The sensors exhibited modest selectivity for acetate but good selectivity for benzoate. The carbazole-derived ionophores effectively decreased the interference from lipophilic anions, such as bromide, nitrate, iodide, and thiocyanate. The selectivity, detection limit, and linear range were improved by choosing a suitable plasticizer and by reducing the ionophore and anion exchanger concentrations. The influence of the electrode body’s material upon the composition of the plasticized poly(vinyl chloride) membrane, and thus also upon the sensor characteristics, was also studied. The choice of materials for the electrode body significantly affected the characteristics of the sensors.

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Beryllium-Ion-Selective PEDOT Solid Contact Electrode Based on 9,10-Dinitrobenzo-9-Crown-3-Ether

Sensors ◽

10.3390/s20216375 ◽

2020 ◽

Vol 20 (21) ◽

pp. 6375

Author(s):

Junghwan Kim ◽

Dae Hee Kim ◽

Jin Cheol Yang ◽

Jae Sang Kim ◽

Ji Ha Lee ◽

...

Keyword(s):

Electrochemical Impedance ◽

Constant Current ◽

Solid Contact ◽

Response Characteristics ◽

Best Response ◽

Wide Ph Range ◽

Selective Membrane ◽

Nernstian Slope ◽

Ph Range ◽

Contact Electrode

A beryllium(II)-ion-selective poly(ethylenedioxythiophene) (PEDOT) solid contact electrode comprising 9,10-dinitrobenzo-9-crown-3-ether was successfully developed. The all-solid-state contact electrode, with an oxygen-containing cation-sensing membrane combined with an electropolymerized PEDOT layer, exhibited the best response characteristics. The performance of the constructed electrode was evaluated and optimized using potentiometry, conductance measurements, constant-current chronopotentiometry, and electrochemical impedance spectroscopy (EIS). Under optimized conditions, which were found for an ion-selective membrane (ISM) composition of 3% ionophore, 30% polyvinylchloride (PVC), 64% o-nitro phenyl octyl ether (o-NPOE), and 3% sodium tetraphenylborate (NaTPB), the fabricated electrode exhibited a good performance over a wide concentration range (10−2.5–10−7.0 M) and a wide pH range of 2.0–9.0, with a Nernstian slope of 29.5 mV/D for the beryllium (II) ion and a detection limit as low as 10−7.0 M. The developed electrode shows good selectivity for the beryllium(II) ion over alkali, alkaline earth, transition, and heavy metal ions.

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Development of a Graphene Paper-Based Flexible Solid-Contact Lead Ion-Selective Electrode and its Application in Water

Transactions of the ASABE ◽

10.13031/trans.12906 ◽

2019 ◽

Vol 62 (2) ◽

pp. 245-252 ◽

Cited By ~ 5

Author(s):

Yao Yao ◽

Yibin Ying ◽

Jianfeng Ping

Keyword(s):

Metal Ion ◽

Water Layer ◽

Potentiometric Sensor ◽

Ion Selective Electrode ◽

Lead Ion ◽

Solid Contact ◽

Selective Electrode ◽

Filtration Method ◽

Selective Membrane ◽

Graphene Paper

Abstract. A graphene paper-based flexible solid-contact ion-selective electrode (SC-ISE) was developed to detect lead ion sensitively. Graphene paper obtained via a simple vacuum filtration method was used as the electrode substrate for direct coating of an ion-selective membrane. The Nernstian slope of the prepared paper-based potentiometric sensor toward lead ion detection was demonstrated as 29.4 mV per decade. A detection limit as low as 2.5 × 10-7 mol L-1 was achieved. Reversed chronopotentiometry and water layer test revealed that the graphene paper-based SC-ISE possessed excellent potential stability because of the hydrophobicity of graphene paper. Furthermore, reliable data were obtained from the detection of lead ion levels in real water samples using the graphene paper-based potentiometric sensor, which shows great potential in practical application. Keywords: Graphene paper, Heavy metal, Ion-selective electrode, Potentiometry, Water sample.

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All Solid-State Poly (Vinyl Chloride) Membrane Potentiometric Sensor Integrated with Nano-Beads Imprinted Polymers for Sensitive and Rapid Detection of Bispyribac Herbicide as Organic Pollutant

Molecules ◽

10.3390/molecules24040712 ◽

2019 ◽

Vol 24 (4) ◽

pp. 712 ◽

Cited By ~ 13

Author(s):

Nashwa Abdalla ◽

Maha Youssef ◽

H. Algarni ◽

Nasser Awwad ◽

Ayman Kamel

Keyword(s):

Solid State ◽

Electrochemical Impedance ◽

Organic Pollutant ◽

Solid Substrate ◽

Hplc Method ◽

Potentiometric Sensors ◽

Pvc Membrane ◽

Aliquat 336 ◽

Solid Contact ◽

Selective Membrane

All-solid-state potentiometric sensors were prepared by using polyaniline (PANI) as the solid contact material. A film of PANI (thickness approximately being 0.25 µm) was deposited on a solid substrate (carbon screen printed platform). The PANI layer was subsequently coated with an ion-selective membrane (ISM) containing uniform-sized molecularly imprinted nanoparticles to produce a solid-contact ion-selective electrode (SC/ISE) for bispyribac herbicide (sensor I). In addition, aliquat 336 was also used as an ion exchanger in plasticized PVC membrane (sensor II). The proposed sensors revealed a remarkably improved sensitivity towards bispyribac ions with anionic slopes of −47.8 ± 1.1 (r2 = 0.9995) and −44.4 ± 1.4 (r2 = 0.9997) mV/decade over a linear range 1.0 × 10−2–8.6 × 10−6 M, 1.0 × 10−2–9.0 × 10−6 M and detection limits of 1.33 and 1.81 µg/mL for sensors I and II, respectively.Selectivity of both sensors is significantly high for different common pesticides and inorganic anions. The potential stability of the SC/ISEs was studied using chronopotentiometry. Electrochemical impedance spectrometry was used to understand the charge-transfer mechanisms of the different types of ion-selective electrodes studied. The impedance response of the electrodes was modelled by using equivalent electrical circuits. The sensors were used for a direct measurement of the bispyribac content in commercial herbicide formulations and soil samples collected from agricultural lands planted with rice and sprayed with bispyribac herbicide. The results agree fairly well with data obtained using HPLC method.

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Application of polyaniline nanofibers for the construction of nitrate all-solid-state ion-selective electrodes

Applied Nanoscience ◽

10.1007/s13204-021-02228-1 ◽

2021 ◽

Author(s):

Karolina Pietrzak ◽

Cecylia Wardak ◽

Szymon Malinowski

Keyword(s):

Electrochemical Impedance ◽

Fast Response ◽

Point Of View ◽

Ion Selective Electrodes ◽

Solid Contact ◽

Measuring Range ◽

Polyaniline Nanofibers ◽

Vis Spectroscopy ◽

Selective Membrane ◽

Nitrate Determination

AbstractThe application of polyaniline nanofibers doped with chloride and nitrate ions (PANINFs-Cl and PANINFs-NO3) in potentiometry was described. Both kinds of nanofibers were used as an ion-to-electron transducer in ion-selective electrodes with solid contact (SCISEs). Extensive research on the properties of the nanofibers themselves (SEM, UV–Vis spectroscopy, FTIR) and the constructed electrodes (potentiometric methods, electrochemical impedance spectroscopy) has been carried out. Basic analytical parameters of electrodes containing various nanofibers contents in the ion-selective membrane and with nanofibers as an intermediate layer were determined. It was found that application of PANI nanofibers resulted in improvement of electrode performance (among others, better stability and reversibility of the electrode potential). The obtained sensors were characterized by a high slope of the calibration curve, a wide measuring range and a fast response time. Moreover, they were insensitive to change of redox potential, as well as light and the presence of oxygen in the solution, what is important from a practical point of view. They were also successfully used for nitrate determination in real environmental samples.

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Ion-to-electron capacitance of single-walled carbon nanotube layers before and after ion-selective membrane deposition

Microchimica Acta ◽

10.1007/s00604-021-04805-1 ◽

2021 ◽

Vol 188 (5) ◽

Author(s):

Elena Zdrachek ◽

Eric Bakker

Keyword(s):

Carbon Nanotube ◽

Ion Selective Electrodes ◽

Solid Contact ◽

Single Walled Carbon Nanotube ◽

Single Walled Carbon ◽

Essential Step ◽

Before And After ◽

Selective Membrane ◽

High Potential Stability ◽

Potential Stability

AbstractThe capacitance of the ion-to-electron transducer layer helps to maintain a high potential stability of solid-contact ion-selective electrodes (SC-ISEs), and its estimation is therefore an essential step of SC-ISE characterization. The established chronopotentiometric protocol used to evaluate the capacitance of the single-walled carbon nanotube transducer layer was revised in order to obtain more reliable and better reproducible values and also to allow capacitance to be measured before membrane deposition for electrode manufacturing quality control purposes. The capacitance values measured with the revised method increased linearly with the number of deposited carbon nanotube–based transducer layers and were also found to correlate linearly before and after ion-selective membrane deposition, with correlation slopes close to 1 for nitrate-selective electrodes, to 0.7 and to 0.5 for potassium- and calcium-selective electrodes. Graphical abstract

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Effects of Ion-Carrier Substituents on the Potentiometric-Response Characteristics in Anion-Selective Membrane Electrodes Based on Iron Porphyrins

ChemPhysChem ◽

10.1002/cphc.200301025 ◽

2004 ◽

Vol 5 (5) ◽

pp. 652-660 ◽

Cited By ~ 8

Author(s):

Saeed Shahrokhian ◽

Hassan Seifi ◽

Mojtaba Bagherzadeh ◽

S. Reza Mousavi

Keyword(s):

Membrane Electrodes ◽

Iron Porphyrins ◽

Response Characteristics ◽

Potentiometric Response ◽

Selective Membrane ◽

Ion Carrier

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Ruthenium dioxide nanoparticles as a high-capacity transducer in solid-contact polymer membrane-based pH-selective electrodes

Microchimica Acta ◽

10.1007/s00604-019-3830-x ◽

2019 ◽

Vol 186 (12) ◽

Cited By ~ 3

Author(s):

Nikola Lenar ◽

Beata Paczosa-Bator ◽

Robert Piech

Keyword(s):

High Capacity ◽

Glass Electrode ◽

Ruthenium Dioxide ◽

Solid Contact ◽

New Approach ◽

Potentiometric Response ◽

Small Resistance ◽

Nernstian Slope ◽

Capacity Transducer ◽

Contact Electrodes

AbstractA new approach is presented for the design of ion selective electrodes. Ruthenium dioxide nanoparticles were incorporated into solid-contact electrodes, and their properties were studied for the case of pH-selective electrodes. The use of the RuO2 is shown to significantly improve the potentiometric response, while no redox response is observed. The use of RuO2 results in a Nernstian slope (59 mV/decade) towards hydrogen ions over a wide linear range (pH 2 to 12). The results obtained by chronopotentiometry reveal small resistance, and the capacitance is as high as 1.12 mF. This results in a good stability of the response and in a low potential drift (0.89 μV∙s−1). The electrodes exhibit properties nearly as excellent as those of a glass electrode, but they are much smaller, less fragile, and easy to use.

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Surface Characterization Studies of Thiols as a Blocking Mechanism for Specific Adsorption for Application of Charge Selective Membrane Transport

Volume 2: Heat Transfer Enhancement for Practical Applications; Fire and Combustion; Multi-Phase Systems; Heat Transfer in Electronic Equipment; Low Temperature Heat Transfer; Computational Heat Transfer ◽

10.1115/ht2012-58573 ◽

2012 ◽

Author(s):

Damena D. Agonafer ◽

Edward Chainani ◽

Muhammed E. Oruc ◽

Ki Sung Lee ◽

Mark A. Shannon

Keyword(s):

Surface Characterization ◽

Electrochemical Impedance ◽

Critical Voltage ◽

Self Assembled Monolayer ◽

Voltage Range ◽

Coated Membranes ◽

Selective Membrane ◽

The Difference ◽

Cv Measurements ◽

Work Done

This paper proposes the use of electrochemical impedance spectroscopy (EIS) to measure characteristics of gold (Au)-coated membranes and their inherent limitations. In this work, the fabrication of a membrane permeate flow cell is described with the aim of subsequently studying the transport of ions through conductive polycarbonate track etched membrane (PCTE) by interrogating the system using EIS and CV measurements. In particular, we would like to ascertain the voltage range that can be applied to the Au-coated membrane without getting a considerable faradaic activity; the difference between platinum and Au electrode; the effects of different electrolyte concentrations and various applied DC potentials. We extend our previous work done [1] by studying the differences of using a hrydroxyl and methyl terminated self assembled monolayer (SAM). We also extend the quality of the monolayer with respect to the amount of time in which the monolayer is grown. Finally, finding the voltage in which a ‘defect free’ monolayer transforms from insulative to ‘leaky’ behavior extends a detailed analysis of the critical voltage of an alkane thiol.

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