scholarly journals Screening Potential of Electrogenic Algae for Bio Power Production from Aquatic Habitats of Tamil Nadu

2021 ◽  
Vol 108 (june) ◽  
pp. 1-5
Author(s):  
Sikkandhar Wasimraja ◽  
◽  
Subburamu Karthikeyan ◽  
Kalyanasundaram Geetha Thanuja ◽  
◽  
...  
Keyword(s):  
Cyclic Voltammetry ◽  
Transport Process ◽  
Tamil Nadu ◽  
Power Production ◽  
Potential Range ◽  
Cyclic Voltammograms ◽  
Oxidation Peak ◽  
Aquatic Habitats ◽  
Anaerobic Conditions ◽  
Extracellular Electron Transport

This paper illustrates the potential ofmicroalgae in electricity production.The present study focuses on searching for, indigenous microalgal strains from various aquatic sources exhibiting electrogenic activity. Sixteen microalgal strains were obtained from the diverse water bodies and assessed for electron transfer ability between cell and electrode. Six algal strains were screened out of eighteen for potential electrogenicity, based on cyclic voltammetry assay. In contrast to other algal strains, the cyclic voltammograms of Hindakia sp. isolated from paddy fields displayed an oxidation peak under anaerobic conditions in the potential range of +100 to +200 mV, while no distinct peaks were observed in other strains. This research broadened the exoelectrogen and identified model microalgae for investigating the extracellular electron transport process.

scholarly journals Electrochemical synthesis of poly(2-methyl aniline): electrochemical and spectroscopic characterization

2001 ◽  
Vol 66 (1) ◽  
pp. 27-37 ◽  
Author(s):  
Aleksandra Buzarovska ◽  
Irena Arsova ◽  
Ljubomir Arsov
Keyword(s):  
Raman Spectroscopy ◽  
Cyclic Voltammetry ◽  
Redox Reactions ◽  
Electrochemical Polymerization ◽  
Spectroscopic Characterization ◽  
Potential Range ◽  
Cyclic Voltammograms ◽  
Impedance Measurements ◽  
Order Of Magnitude ◽  
Poly Aniline

Poly(2-methyl aniline) or poly(ortho-toluidine), as ring substituted derivative of aniline, has been synthesized electrochemically in various concentrations of H2SO4 and HCl, and then characterized by cyclic voltammetry, as well as by impedance and Raman spectroscopy. The cyclic voltammograms of poly(o-toluidine) and poly(aniline) show that the electrochemical polymerization of these two polymers proceeds by almost identical mechanisms. The Raman spectroscopical measurements suggest that the redox reactions of poly(aniline) and poly(o-toluidine) are similar in the potential range between -0.2 and 0.7V vs. SCE. The impedance measurements showed that the conductivity of poly(o-toluidine) is an order of magnitude lower than that of the corresponding poly(aniline) form.

Elektrochemisches Verhalten der Nitrophenole und ihrer Reduktionsprodukte an Graphitelektroden/ Electrochemical Behavior of the Nitrophenols and Their Reduction Products at Graphite Electrodes

1981 ◽  
Vol 36 (7) ◽  
pp. 840-845 ◽  
Author(s):  
Elli Theodoridou ◽  
Dimitrios Jannakoudakis
Keyword(s):  
Aqueous Solutions ◽  
Electrochemical Behavior ◽  
Ph Dependence ◽  
Chemical Oxidation ◽  
Potential Range ◽  
Cyclic Voltammograms ◽  
Hanging Mercury Drop Electrode ◽  
Oxidation Peak ◽  
Graphite Electrodes ◽  
Reduction Potentials

Abstract The electrochemical reduction of the isomeric nitrophenols at graphite electrodes is investigated in aqueous solutions with pH = 1-13 and is compared with the electro-chemical oxidation of their reduction products. o-Nitrophenol and p-nitrophenol are reduced to the corresponding amines, as the observed oxidation peaks in their cyclic voltammograms can be simulated by those of o-and p-aminophenol. m-Nitrophenol is reduced to m-hydroxylaminophenol, as its oxidation peak appears at much more negative » potential than that of m-aminophenol, within the potential range of the oxidation of phenylhydroxylamine. The pH-dependence of the reduction potentials of the nitrophenols at the graphite electrodes is discussed in comparison with that at a hanging mercury drop electrode.

Laser Photocatalysis of the Chlorophyll Dye Using the Cyclic Voltammetry Method

2021 ◽  
Vol 882 ◽  
pp. 143-154
Author(s):  
Huda S. Alhasan
Keyword(s):  
Cyclic Voltammetry ◽  
Laser Light ◽  
Potential Range ◽  
Carbon Electrode ◽  
Total Chlorophyll ◽  
Tetrabutylammonium Perchlorate ◽  
Oxidation Peak ◽  
Solution Ph ◽  
Cyclic Voltammetry Method ◽  
Wide Potential

Cyclic voltammetry is a widely used technique in electrochemistry due to its simplicity and large amount of data and information that can be obtained. This study utilises this technique to study chlorophyll a and total chlorophyll (Tchl) alongside a laser light to induce photosynthesis. No oxidative peak was observed, regardless of the solution pH in either a dark or light environment when using a solution with an electrolyte of tetrabutylammonium perchlorate (TBAP) in both dichloromethane (DCM) and acetonitrile (MeCN), whereas in a solution of aqueous HCl a small anodic peak was observed. The concentration of the droplet of Tchl pigment on the surface of macro glassy carbon electrode (GCE) was increased, which resulted in a similar trend and the oxidation peak was observed to be slightly larger when in the presence of light. It was observed that the filtered solution of Tchl pigment produced a weaker signal than the unfiltered solution and there were slightly reduced oxidative peak currents when the concentration of VK1 was increased. were no observed changes in the peak charges or currents over a wide potential range (0.0, 0.2, 0.4, 0.6 and 0.8 V) in the presence or absence of light by using coulometry and amperometry methods, therefore, more information on the 3-D formation is required for the photoreduction processes.

Electrochemical behaviour of silver in aqueous chromate solutions

1998 ◽  
Vol 76 (8) ◽  
pp. 1156-1161 ◽  
Author(s):  
Sayed S Abd El Rehim ◽  
Magdy AM Ibrahim ◽  
Hamdy H Hassan ◽  
Mohammed A Amin
Keyword(s):  
Cyclic Voltammetry ◽  
Electrochemical Behaviour ◽  
Anode Surface ◽  
Cyclic Voltammograms ◽  
Oxidation Peak ◽  
Surface Layers ◽  
Compact Layer ◽  
X Ray ◽  
Solid Films ◽  
Scan Rate

The electrochemical behaviour of silver was studied under cyclic voltammetry and chronoamperometry conditions in aqueous K2CrO4 solutions. The forward cyclic voltammograms exhibited one oxidation peak, A1, due to the formation of Ag2CrO4. The height of the anodic peak, A1, increases with increasing chromate concentration, temperature, and scan rate. The solid films formed on the anode surface have been examined by X-ray diffractometry. The reverse voltammograms exhibited two reduction peaks, C1 and C2, indicating the formation of two distinct surface layers of Ag2CrO4, an inner compact layer reduced in peak C1 and an outer powdery layer reduced in peak C2.Key words: silver electrode, cyclic voltammetry, K2CrO4 solutions.

scholarly journals Reduced Graphene Oxide Fibre Electrodes for Drug Sensing

Proceedings ◽  
2021 ◽  
Vol 68 (1) ◽  
pp. 18
Author(s):  
Sutthima Sriprasertsuk ◽  
John R. Varcoe ◽  
Carol Crean
Keyword(s):  
Cyclic Voltammetry ◽  
Graphene Oxide ◽  
Carbon Fibre ◽  
Reduced Graphene Oxide ◽  
Limit Of Detection ◽  
Linear Range ◽  
Oxidation Peak ◽  
Reduced Graphene ◽  
Fibre Sensor ◽  
Model Drug

Reduced graphene oxide (rGO) fibre electrodes and their ability to sense paracetamol (as model drug) were studied. rGO was electrodeposited onto carbon fibre by two different approaches: potentiostatic deposition and cyclic voltammetry (CV) in the presence of graphene oxide solution. Carbon fibre electrodes coated with rGO (after five CV cycles) could sense paracetamol with an oxidation peak at 0.62 V (vs. Ag/AgCl). The limit of detection of this fibre sensor was found to be 36.3 µM with a linear range of 50–500 µM of paracetamol (R2 = 0.9901).

Polyaniline: Influence of Polymerization Current Density

1994 ◽  
Vol 369 ◽  
Author(s):  
Steen Skaarup ◽  
L.M.W.K. Gunaratne ◽  
Keld West ◽  
Birgit Zachau-Christiansen
Keyword(s):  
Cyclic Voltammetry ◽  
Current Density ◽  
High Current Density ◽  
Electrochemical Polymerization ◽  
Regular Structure ◽  
Spectral Lines ◽  
Complex Nature ◽  
Cyclic Voltammograms ◽  
Layer By Layer ◽  
Current Densities

AbstractPolyaniline has been synthesized in propylene carbonate by galvanostatic electrochemical polymerization at current densities between 16 and 1000 μA/cm2. Earlier results for polypyrrole have shown that low and high current density films have different properties: The films synthesized at low current density have a higher conjugation length and a more regular structure. The corresponding effect in PANI has been investigated by cyclic voltammetry and UV/visible spectroscopy. Simultaneous measurement of cyclic voltammograms and the absorbtion of selected spectral lines is used because of the complex nature of the PANI system which involves several redox systems as well as forms differing in the degree of protonation and morphology.The main result is that the method of galvanostatic synthesis at low current densities (-16 μA/cm2) produces polyaniline polymers of different, more conjugated and more regular structure than those prepared at higher current densities. The standard method of in situ layer-by-layer polymerization of conducting polymers during cyclic voltammetry often results in uncontrolled and unmeasured current densities of 0.5-2 mA/cm2 which produces a film that probably has a less regular structure containing more deviations from ideality.

scholarly journals Investigations on the Redox Characteristics and Hydrogen Evolution Efficiencies of Pd and Mo Deposited Pd Electrodes in Alkaline Electrolyte

1970 ◽  
Vol 43 (1) ◽  
pp. 103-116 ◽  
Author(s):  
M Ashraful Islam Molla ◽  
Mithun Sarker ◽  
AKM Fazle Kibria
Keyword(s):  
Hydrogen Evolution ◽  
Hydrogen Adsorption ◽  
Stable Condition ◽  
Alkaline Electrolyte ◽  
Potential Range ◽  
Cyclic Voltammograms ◽  
Absorption Region ◽  
Potential Value ◽  
Density Values ◽  
Hydrogen Evolution Reactions

Redox behaviors and hydrogen evolution efficiencies of Pd and Mo deposited Pd electrodes have been investigated in 30wt.% KOH electrolyte by cyclic voltammetry. Cyclic voltammograms of Pd electrode in between the potential range - 1.05 V to + 0.75 V showed two couples of redox peaks for the transformations of Pd(0) ←→ Pd(OH)2 and Pd(OH)2 ←→ PdOOH, an anodic peak for the desorption of diffusional hydrogen (dH) and hydrogen and oxygen evolutions at the terminal potential regions. Hydrogen evolution efficiency found decreased with time and then reached to a stable condition after 35 minutes. In presence of deposited Mo, the electrode stable condition appeared after 10 minutes only. Pd found predominates over deposited Mo. Both the Pd(0) ←Pd(OH)2 and Mo(0) ← Mo(OH)2 transformations appeared at the same potential value. Mo stopped the movement of hydrogen adsorption and absorption region of Pd electrode towards negative potential direction. It increased the hydrogen evolution efficiency of Pd electrode remarkably. At the potentials - 1.1 V, - 1.2 V, - 1.25 V and - 1.3 V, currents for Pd + Mo system found 1.44, 1.25, 1.20, 1.23 times higher than those of Pd electrode. Mo also showed hydrogen migratory role to the fraction of Pd surface covered by it. Hydrogen evolution reactions (HER) over Pd and Pd + Mo surfaces seemed followed similar mechanisms. Tafel plots for the HER for both the systems showed two Tafel regions. Exchange current density values (io) for the low and high overpotential regions of Pd + Mo system showed 2.85 times and 1.29 times higher values than those of Pd electrode. Key words: Pd, Pd-Mo, Hydrogen evolution efficiency, Hydrogen evolution reactions (HER) DOI: 10.3329.bjsir.v43i1.861 Bangladesh J. Sci. Ind. Res. 43(1), 103-116, 2008

Interaction between Binuclear Copper(I) Complexes and the Dioxygen Molecule Investigated by Electrochemical Methods

1992 ◽  
Vol 47 (1) ◽  
pp. 109-114 ◽  
Author(s):  
Yuzo Nishida ◽  
Izumi Watanabe ◽  
Kei Unoura
Keyword(s):  
Cyclic Voltammetry ◽  
Thin Layer ◽  
Electrochemical Reduction ◽  
High Reactivity ◽  
Electrochemical Methods ◽  
Tridentate Ligand ◽  
Cyclic Voltammograms ◽  
Binuclear Copper ◽  
Alkyl Chains ◽  
Binucleating Ligands

The cyclic voltammograms of some binuclear copper(II) compounds with binucleating ligands where two molecules of tridentate ligand, N, N -bis(benzimidazol-2-ylmethyl)amine are linked by several alkyl chains, were measured under both argon and dioxygen. The results demonstrate that the binuclear copper(I) species produced by electrochemical reduction exhibit high reactivity towards dioxygen, while the reaction of the corresponding mononuclear species with oxygen is very slow. Thin-layer coulometry ([binuclear copper(I)]/[O2] = 0.47 - 10.6) and thin-layer cyclic voltammetry ([binuclear copper(I)]/[O2] = 4.3 - 10.6 ) revealed that two molecules of the binuclear copper(I) species react with one molecule of dioxygen.

scholarly journals Polypyrrole–Nickel Hydroxide Hybrid Nanowires as Future Materials for Energy Storage

Nanomaterials ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 307 ◽  
Author(s):  
Agnieszka Brzózka ◽  
Krzysztof Fic ◽  
Joanna Bogusz ◽  
Anna Brudzisz ◽  
Mateusz Marzec ◽  
...  
Keyword(s):  
Cyclic Voltammetry ◽  
Energy Storage ◽  
Nickel Hydroxide ◽  
Photoelectron Spectroscopy ◽  
Nanowire Array ◽  
Potential Range ◽  
Cyclic Stability ◽  
X Ray ◽  
Sem And Tem ◽  
Array Electrode

Hybrid materials play an essential role in the development of the energy storage technologies since a multi-constituent system merges the properties of the individual components. Apart from new features and enhanced performance, such an approach quite often allows the drawbacks of single components to be diminished or reduced entirely. The goal of this paper was to prepare and characterize polymer-metal hydroxide (polypyrrole-nickel hydroxide, PPy-Ni(OH)2) nanowire arrays demonstrating good electrochemical performance. Nanowires were fabricated by potential pulse electrodeposition of pyrrole and nickel hydroxide into nanoporous anodic alumina oxide (AAO) template. The structural features of as-obtained PPy-Ni(OH)2 hybrid nanowires were characterized using FE-SEM and TEM analysis. Their chemical composition was confirmed by energy-dispersive x-ray spectroscopy (EDS). The presence of nickel hydroxide in the synthesized PPy-Ni(OH)2 nanowire array was investigated by X-ray photoelectron spectroscopy (XPS). Both FE-SEM and TEM analyses confirmed that the obtained nanowires were composed of a polymer matrix with nanoparticles dispersed within. EDS and XPS techniques confirmed the presence of PPy-Ni(OH)2 in the nanowire array obtained. Optimal working potential range (i.e., available potential window), charge propagation, and cyclic stability of the electrodes were determined with cyclic voltammetry (CV) at various scan rates. Interestingly, the electrochemical stability window for the aqueous electrolyte at PPy-Ni(OH)2 nanowire array electrode was remarkably wider (ca. 2 times) in comparison with the non-modified PPy electrode. The capacitance values, calculated from cyclic voltammetry performed at 20 mV s−1, were 25 F cm−2 for PPy and 75 F cm−2 for PPy-Ni(OH)2 array electrodes. The cyclic stability of the PPy nanowire array electrode up to 100 cycles showed a capacitance fade of about 13%.

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