Cyclic voltammetry test for the effectiveness of cathode additives in the sodium-sulphur battery

By using pulse cyclic voltammetry rather than cyclic voltammetry at a relatively high scan rate, an increase in sensitivity and a lowering of the detection limit by more than a factor of two are demonstrated for the ferricyanide–ferrocyanide couple at a carbon electrode. The test for reversibility based on peak shape or symmetry comparison is enhanced significantly with pulse cyclic voltammetry. Another reversibility test, by observing peak variations as a function of scan rate, was applied to pulse cyclic voltammetry and was found to be as diagnostically informative as the cyclic voltammetry test. These tests are illustrated by a study of the hydroquinone–quinone couple.

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Nanocarbon from Rice Straw as Supercapacitor Electrode

Materials Science Forum ◽

10.4028/www.scientific.net/msf.964.180 ◽

2019 ◽

Vol 964 ◽

pp. 180-184

Author(s):

Michael Lianto ◽

Sulistiyawati Dewi Kiniasih ◽

Irma Septi Ardiani ◽

Malik Anjelh Baqiyah ◽

Vania Mitha Pratiwi

Keyword(s):

Cyclic Voltammetry ◽

Solid State ◽

Rice Straw ◽

Active Carbon ◽

Solid State Reaction ◽

Milling Process ◽

Raw Material ◽

Supercapacitor Electrode ◽

Cyclic Voltammetry Test

Rice straw waste in Indonesia is abundant and not yet used optimally. The composition of rice straw is 40% cellulose, 30% hemicellulose, 15% silica and 15% lignin so it is potentially to be a raw material of active carbon and supercapasitor electrode. Many efforts has been done to increase the value of capacitance of electrode like increase the surface area with activation and milling process. In this research used the variation of activator substance and the variation of milling velocity, they are H3PO4 450 rpm, H3PO4 600 rpm, and KOH 450 rpm. The purposes of this research are identify and characterize the rice straw charcoal material as nanocarbon and also knowing the nanocarbon quality of rice straw charcoal material as supercapacitor electrode. The methods are carbonization, activation, and solid state reaction. The result of this research shows the value of capacitance at H3PO4 450 rpm, H3PO4 600 rpm, and KOH 450 rpm are 28,96 F/g; 30,89 F/g; dan 19,31 F/g. From this research, we can conclude that activator substance and milling velocity affect the value of capacitance that is produced. The result of SEM-EDX test is comparable with the result of cyclic voltammetry test, the higher number of pores the higher value of capacitances produced.

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An Electroactive Polymer Modified Separator with A Potential Clamp Function

MATEC Web of Conferences ◽

10.1051/matecconf/201823805005 ◽

2018 ◽

Vol 238 ◽

pp. 05005

Author(s):

Kaiyue Zhang ◽

Wei Xiao ◽

Jianguo Liu ◽

Chuanwei Yan

Keyword(s):

Cyclic Voltammetry ◽

Oxidative Polymerization ◽

Electroactive Polymer ◽

Chemical Oxidative Polymerization ◽

Uniform Coating ◽

Constant Potential ◽

Current Densities ◽

Composite Separator ◽

Cyclic Voltammetry Test ◽

Modified Separator

An inexpensive electroactive polymer polytriphenylamine (PTPAn) was synthesized through chemical oxidative polymerization of TPA. The composite separator was simply prepared by impregnating a commercial PP separator with PTPAn polymer solution. PTPAn was observed on the surface of the composite separator and formed a uniform coating. In cyclic voltammetry test, PTPAn polymer exhibited a pair of well-defined redox peaks between 3.0 and 4.5 V, which could be regarded as a reversible electrochemical p-doping and dedoping process. When incorporated in a blocking cell, the composite separator was able to hold a constant potential for current densities up to 5 mA/cm2 to protect the cell from overcharging.

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Using cyclic voltammetry to determine the protective ability of phosphate coatings

Functional materials ◽

10.15407/fm27.03.605 ◽

2020 ◽

Vol 27 (3) ◽

Keyword(s):

Cyclic Voltammetry ◽

Protective Ability ◽

Phosphate Coatings

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Photochemical and Electrochemical Reduction of Carbon Dioxide Catalyzed by a Polyoxometalate-Organic Photosensitizer Complex

10.26434/chemrxiv.7177892 ◽

2018 ◽

Author(s):

Chandan Dey ◽

Ronny Neumann

Keyword(s):

Carbon Dioxide ◽

Cyclic Voltammetry ◽

Formic Acid ◽

Electrochemical Reduction ◽

Mass Spectroscopy ◽

Photochemical Reactions ◽

Reducing Agent ◽

Covalent Attachment ◽

Hybrid Complex ◽

Open Face

A manganese substituted Anderson type polyoxometalate, [MnMo6O24]9-, tethered with an anthracene photosensitizer was prepared and used as catalyst for CO2 reduction. The polyoxometalate-photosensitizer hybrid complex, obtained by covalent attachment of the sensitizer to only one face of the planar polyoxometalate, was characterized by NMR, IR and mass spectroscopy. Cyclic voltammetry measurements show a catalytic response for the reduction of carbon dioxide, thereby suggesting catalysis at the manganese site on the open face of the polyoxometalate. Controlled potentiometric electrolysis showed the reduction of CO2 to CO with a TOF of ~15 sec-1. Further photochemical reactions showed that the polyoxometalate-anthracene hybrid complex was active for the reduction of CO2 to yield formic acid and/or CO in varying amounts dependent on the reducing agent used. Control experiments showed that the attachment of the photosensitizer to [MnMo6O24]9- is necessary for photocatalysis.<div> </div>

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Endgroup and Sidechain Functionalization of Surface-Initiated ROMP Thin Films: Progress Towards ROMP-Based Molecular Wires

10.26434/chemrxiv.5954518 ◽

2018 ◽

Author(s):

Nicholas Marshall

Keyword(s):

Thin Films ◽

Contact Angle ◽

Cyclic Voltammetry ◽

Polymer Films ◽

Conjugated Polymer ◽

Ring Opening ◽

Molecular Wires ◽

Metathesis Polymerization ◽

Cross Metathesis ◽

Active Ester

A set of experiments in surface-initiated ring-opening metathesis polymerization, including end-functionalization of growing brushes and contact angle/cyclic voltammetry measurements. We report preparation and CV of two different conjugated polymer films, and several endgroup and sidechain functionalization experiments using cross-metathesis and active ester substitution.

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Exploration of Bis(Arylimidazole) Iridium Picolinate Complexes

10.26434/chemrxiv.5331460.v1 ◽

2017 ◽

Cited By ~ 1

Author(s):

Aron Huckaba ◽

sadig aghazada ◽

iwan zimmermann ◽

giulia grancini ◽

natalia gasilova ◽

...

Keyword(s):

Cyclic Voltammetry ◽

Photophysical Properties ◽

Structure Property ◽

Aryl Group ◽

Ligand Modification ◽

Property Relationship ◽

Structure Property Relationship

The straightforward synthesis and photophysical properties of a new series of heteroleptic Iridium (III) bis(2-arylimidazole) picolinate complexes is reported. Each complex has been characterized by NMR, UV-Vis, cyclic voltammetry, and the emissive properties of each is described. By systematically modifying first the cyclometallating aryl group on the arylimidazole ligand and then the picolinate ligand, the ramifications of ligand modification in these complexes was better understood through the construction of a structure-property relationship.

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Exploration of Bis(Arylimidazole) Iridium Picolinate Complexes

10.26434/chemrxiv.5331460 ◽

2017 ◽

Author(s):

Aron Huckaba ◽

sadig aghazada ◽

iwan zimmermann ◽

giulia grancini ◽

natalia gasilova ◽

...

Keyword(s):

Cyclic Voltammetry ◽

Photophysical Properties ◽

Structure Property ◽

Aryl Group ◽

Ligand Modification ◽

Property Relationship ◽

Structure Property Relationship

The straightforward synthesis and photophysical properties of a new series of heteroleptic Iridium (III) bis(2-arylimidazole) picolinate complexes is reported. Each complex has been characterized by NMR, UV-Vis, cyclic voltammetry, and the emissive properties of each is described. By systematically modifying first the cyclometallating aryl group on the arylimidazole ligand and then the picolinate ligand, the ramifications of ligand modification in these complexes was better understood through the construction of a structure-property relationship.

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Experimental Assessment of the Practical Oxidative Stability of Lithium Thiophosphate Solid Electrolytes

10.26434/chemrxiv.8014715.v1 ◽

2019 ◽

Author(s):

Georg Dewald ◽

Saneyuki Ohno ◽

Marvin Kraft ◽

Raimund Koerver ◽

Paul Till ◽

...

Keyword(s):

Cyclic Voltammetry ◽

Solid State ◽

Oxidative Stability ◽

Photoelectron Spectroscopy ◽

Solid Electrolytes ◽

Stability Limit ◽

Lithium Ion ◽

High Energy ◽

Redox Activity ◽

Solid State Batteries

All-solid-state batteries are often expected to replace conventional lithium-ion batteries in the future. However, the practical electrochemical and cycling stability of the best-conducting solid electrolytes, i.e. lithium thiophosphates, are still critical issues that prevent long-term stable high-energy cells. In this study, we use stepwisecyclic voltammetry to obtain information on the practical oxidative stability limit of Li10GeP2S12, a Li2S‑P2S5glass, as well as the argyrodite Li6PS5Cl solid electrolytes. We employ indium metal and carbon black as the counter and working electrode, respectively, the latter to increase the interfacial contact area to the electrolyte as compared to the commonly used planar steel electrodes. Using a stepwise increase in the reversal potentials, the onset potential at 25 °C of oxidative decomposition at the electrode-electrolyte interface is identified. X‑ray photoelectron spectroscopy is used to investigate the oxidation of sulfur(-II) in the thiophosphate polyanions to sulfur(0) as the dominant redox process in all electrolytes tested. Our results suggest that after the formation of these decomposition products, significant redox behavior is observed. This explains previously reported redox activity of thiophosphate solid electrolytes, which contributes to the overall cell performance in solid-state batteries. The stepwise cyclic voltammetryapproach presented here shows that the practical oxidative stability at 25 °C of thiophosphate solid electrolytes against carbon is kinetically higher than predicted by thermodynamic calculations. The method serves as an efficient guideline for the determination of practical, kinetic stability limits of solid electrolytes.

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Experimental Assessment of the Practical Oxidative Stability of Lithium Thiophosphate Solid Electrolytes

10.26434/chemrxiv.8014715 ◽

2019 ◽

Author(s):

Georg Dewald ◽

Saneyuki Ohno ◽

Marvin Kraft ◽

Raimund Koerver ◽

Paul Till ◽

...

Keyword(s):

Cyclic Voltammetry ◽

Solid State ◽

Oxidative Stability ◽

Photoelectron Spectroscopy ◽

Solid Electrolytes ◽

Stability Limit ◽

Lithium Ion ◽

High Energy ◽

Redox Activity ◽

Solid State Batteries

All-solid-state batteries are often expected to replace conventional lithium-ion batteries in the future. However, the practical electrochemical and cycling stability of the best-conducting solid electrolytes, i.e. lithium thiophosphates, are still critical issues that prevent long-term stable high-energy cells. In this study, we use stepwisecyclic voltammetry to obtain information on the practical oxidative stability limit of Li10GeP2S12, a Li2S‑P2S5glass, as well as the argyrodite Li6PS5Cl solid electrolytes. We employ indium metal and carbon black as the counter and working electrode, respectively, the latter to increase the interfacial contact area to the electrolyte as compared to the commonly used planar steel electrodes. Using a stepwise increase in the reversal potentials, the onset potential at 25 °C of oxidative decomposition at the electrode-electrolyte interface is identified. X‑ray photoelectron spectroscopy is used to investigate the oxidation of sulfur(-II) in the thiophosphate polyanions to sulfur(0) as the dominant redox process in all electrolytes tested. Our results suggest that after the formation of these decomposition products, significant redox behavior is observed. This explains previously reported redox activity of thiophosphate solid electrolytes, which contributes to the overall cell performance in solid-state batteries. The stepwise cyclic voltammetryapproach presented here shows that the practical oxidative stability at 25 °C of thiophosphate solid electrolytes against carbon is kinetically higher than predicted by thermodynamic calculations. The method serves as an efficient guideline for the determination of practical, kinetic stability limits of solid electrolytes.

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