scholarly journals A Comparative Study of the Anion Transfer Kinetics Across a Water/Nitrobenzene Interface by Means of Electrochemical Impedance Spectroscopy and Square-Wave Voltammetry at Thin Organic Film-Modified Electrodes

Langmuir ◽  
2006 ◽  
Vol 22 (7) ◽  
pp. 3404-3412 ◽  
Author(s):  
Rubin Gulaboski ◽  
Valentin Mirćeski ◽  
Carlos M. Pereira ◽  
M. Natalia D. S. Cordeiro ◽  
A. Fernando Silva ◽  
...  
Keyword(s):  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Comparative Study ◽  
Square Wave Voltammetry ◽  
Electrochemical Impedance ◽  
Modified Electrodes ◽  
Organic Film ◽  
Square Wave ◽  
Wave Voltammetry ◽  
Anion Transfer

scholarly journals Development of polyindole/tungsten carbide nanocomposite-modified electrodes for electrochemical quantification of chlorpyrifos

2019 ◽  
Vol 10 (1) ◽  
pp. 33-45 ◽  
Author(s):  
Pragati Joshi ◽  
Sameena Mehtab ◽  
M. G. H. Zaidi ◽  
Tanvi Tyagi ◽  
Anjali Bisht
Keyword(s):  
Square Wave Voltammetry ◽  
Electrochemical Impedance ◽  
Stainless Steel Substrate ◽  
Steel Substrate ◽  
Modified Electrodes ◽  
Polymer Nanocomposite ◽  
Square Wave ◽  
Wave Voltammetry ◽  
Viable Method ◽  
Detection And Quantification

Abstract The present investigation deals with the development of a novel polymer nanocomposite (PNCs) electrodes for simple, selective and sensitive detection of chlorpyrifos (CHL). PNCs were developed using surfactant facilitated polymerization of indole using different concentrations (wt%) of WC ranging 5–30. Formation of PNCs was ascertained through diversified analytical methods. Electrodes were derived from PNCs over stainless steel substrate for electrochemical quantification of CHL. With concentration of WC, the DC conductivity (10−2 × S/cm) of electrodes was increased ranging 3.54–0.75 at 313 K. Electrochemical impedance spectroscopy reveals well stability of electrodes in phosphate buffer (PBS, 0.1 M) at pH 7.4. The performance of electrodes towards detection and quantification of CHL was investigated through square wave voltammetry. Study reveals that detection and quantification of CHL were dependent on concentration of WC in nanocomposites. Square wave voltammetry reveals that the electrode derived from PNCs with 5 wt% of WC has rendered highest limits of detection and quantification of CHL (10−8 mol/L) up to 5.94 and 18. This work describes a viable method of preparation of synergistic blend of WC in PIN matrix having high electrical conductivity, rapid electron shift, huge surface area and enhanced stability for fast and précised electrochemical detection of CHL. Graphic abstract

scholarly journals Electrochemical Detection of Phenanthrene Using Nickel Oxide Doped PANI Nanofiber Based Modified Electrodes

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Omolola E. Fayemi ◽  
Abolanle S. Adekunle ◽  
Eno E. Ebenso
Keyword(s):  
Nickel Oxide ◽  
Square Wave Voltammetry ◽  
Modified Electrodes ◽  
Oxidation Potential ◽  
Current Response ◽  
Modified Glassy Carbon Electrode ◽  
Square Wave ◽  
Wave Voltammetry ◽  
Doped Polyaniline ◽  
Uv Visible

A nickel oxide doped polyaniline nanofibers (PANI-NiO) based electrochemical sensor was constructed for detection of phenanthrene. Successful synthesis of PANI-NiO nanocomposite was confirmed with techniques such as SEM, XRD, EDX, FTIR, and UV-visible spectroscopy. The electrocatalytic oxidation of phenanthrene on PANI-NiO on modified glassy carbon electrode (GCE-PANI-NiO) was studied using cyclic voltammetry, square wave voltammetry, and impedance spectroscopy and discussed. Results showed that detection of phenanthrene was enhanced by the nanostructure of PANI-NiO film. The square wave voltammetry analysis shows a very low detection limit of 0.732 pM for phenanthrene with the linear range of 7.6 pM–1.4 × 10−11 M. The Tafel value of 227 mVdec−1suggests adsorption of phenanthrene oxidation intermediates on the GCE-PANI-NiO electrode. The GCE-PANI-NiO modified electrodes gave better performance towards phenanthrene in terms of current response, oxidation potential, current recovery, stability, and resistance to electrode fouling effects.

scholarly journals Degradation Phenomena of Bismuth-Modified Felt Electrodes in VRFB Studied by Electrochemical Impedance Spectroscopy

Batteries ◽  
2019 ◽  
Vol 5 (1) ◽  
pp. 16 ◽  
Author(s):  
Jonathan Schneider ◽  
Eduard Bulczak ◽  
Gumaa El-Nagar ◽  
Marcus Gebhard ◽  
Paul Kubella ◽  
...  
Keyword(s):  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Electrochemical Impedance ◽  
Modified Electrodes ◽  
Impregnation Method ◽  
Carbon Felt ◽  
Half Cell ◽  
Negative Side ◽  
Prolonged Contact ◽  
Before And After

The performance of all-V redox flow batteries (VRFB) will decrease when they are exposed to dynamic electrochemical cycling, but also when they are in prolonged contact with the acidic electrolyte. These phenomena are especially severe at the negative side, where the parasitic hydrogen evolution reaction (HER) will be increasingly favored over the reduction of V(III) with ongoing degradation of the carbon felt electrode. Bismuth, either added to the electrolyte or deposited onto the felt, has been reported to suppress the HER and therefore to enhance the kinetics of the V(II)/V(III) redox reaction. This study is the first to investigate degradation effects on bismuth-modified electrodes in the negative half-cell of a VRFB. By means of a simple impregnation method, a commercially available carbon felt was decorated with Bi 2 O 3 , which is supposedly present as Bi(0) under the working conditions at the negative side. Modified and unmodified felts were characterized electrochemically using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in a three-electrode setup. Surface morphology of the electrodes and composition of the negative half-cell electrolyte were probed using scanning electron microscopy (SEM) and X-ray fluorescence spectroscopy (TXRF), respectively. This was done before and after the electrodes were subjected to 50 charge-discharge cycles in a battery test bench. Our results suggest that not only the bismuth catalyst is dissolved from the electrode during battery operation, but also that the presence of bismuth in the system has a strong accelerating effect on electrode degradation.

Sign in / Sign up

Export Citation Format

Share Document