La dissolution du chlorure cuivreux formé par oxydation électrochimique du cuivre

1982 ◽  
Vol 60 (5) ◽  
pp. 616-623 ◽  
Author(s):  
Robert-Louis Brossard
Keyword(s):  
Copper Chloride ◽  
Ionic Species ◽  
Open Circuit ◽  
Complete Disappearance ◽  
Rotating Disc ◽  
Electrode Voltage ◽  
Stationary Electrode ◽  
Local Enrichment ◽  
Rapid Drop ◽  
A Current

We have studied the dissolution of copper chloride formed by the electrochemical oxidation of copper immersed in aqueous lithium chloride. The pH was maintained between 3 and 5 while the concentration of LiCl in solution was varied between 2.36 × 10−2 M to 16.5 × 10−2 M. The corrosion product accumulating on the electrode consists of crystals of nantokite (CuCl) formed by precipitation.The presence of this precipitate contributes to the local enrichment of the solution which is close to saturation near the electrode. This enrichment is revealed by an electrode voltage in a well characterized open circuit. This current is about −40 mV (/ECS) on a stationary electrode. The complete dissolution of CuCl coincides with a rapid drop in voltage which allows the transition time τ to be defined from which the speed of dissolution of CuCl has been calculated. For example, the speed of dissolution is 0.15 ± 0.01 mC s−1 cm2 in a current equivalent for a stationary electrode in the presence of 2.36 × 10−2 M of dissolved LiCl. This is also constant until the complete disappearance of the precipitate.In another study, the use of a rotating disc electrode shows that the dissolution is completely dominated by the diffusion of ionic species in the liquid phase. The experimental results are compatible with the presence of CuCl2− as the diffusing species. [Journal Translation]

Etude de la dissolution du bromure cuivreux formé sur le cuivre

1984 ◽  
Vol 62 (6) ◽  
pp. 1112-1119 ◽  
Author(s):  
Robert-Louis Brossard
Keyword(s):  
Corrosion Product ◽  
Open Circuit ◽  
Complete Disappearance ◽  
Rotating Disc ◽  
Rapid Fall ◽  
Stationary Electrode ◽  
Definition Of ◽  
Local Enrichment ◽  
Almost All ◽  
A Current

The dissolution of cuprous bromide, formed by the electrochemical oxidation of copper immersed in aqueous NaBr, has been studied. NaBr concentration was varied between 0.1 and 1.2 M at pH 4. The corrosion product accumulating on the electrode is crystalline γ-CuBr. The presence of this material contributes to the local enrichment of dissolved copper close to the electrode. This enrichment leads to a characteristic electrode voltage in open circuit, which is about −149 mV (ECS) at a stationary electrode immersed in a solution of 0.2 M NaBr. The complete dissolution of CuBr coincides with a rapid fall in voltage which permits the definition of the transition time τ from which the speed of CuBr dissolution has been calculated. For example, the speed of dissolution is 0.074 ± 0.003 mA cm−2 in a current equivalent for a stationary electrode in the presence of a non-stirred solution of 0.2 M NaBr. This is constant until the complete disappearance of the CuBr. On the other hand, use of a rotating disc electrode demonstrates that the dissolution is entirely dominated by the diffusion of ions in the liquid phase. The experimental results are compatible with the simultaneous presence of [Formula: see text] and [Formula: see text] as diffusing species. Finally, the potentiodynamic polarization curves show two oxidation waves. A non-negligible portion of the dissolution current, if not almost all, is associated with the formation of CuBr as the sole corrosion product on the electrode. [Journal translation]

scholarly journals Fabrication and Testing of All-solid-state Nanoscale Lithium Batteries Using LiPON for Electrolytes

2018 ◽  
Vol 53 ◽  
pp. 01008
Author(s):  
Feihu Tan ◽  
XiaoPing Liang ◽  
Feng Wei ◽  
Jun Du
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Solid State ◽  
Magnetron Sputtering ◽  
Specific Capacity ◽  
Rf Magnetron Sputtering ◽  
Open Circuit ◽  
Working Pressure ◽  
Thin Film Battery ◽  
A Current

The amorphous LiPON thin film was obtained by using the crystalline Li3PO4 target and the RF magnetron sputtering method at a N2 working pressure of 1 Pa. and then the morphology and composition of LiPON thin films are analysed by SEM and EDS. SEM shows that the film was compact and smooth, while EDS shows that the content of N in LiPON thin film was about 17.47%. The electrochemical properties of Pt/LiPON/Pt were analysed by EIS, and the ionic conductivity of LiPON thin films was 3.8×10-7 S/cm. By using the hard mask in the magnetron sputtering process, the all-solid-state thin film battery with Si/Ti/Pt/LiCoO2/LiPON/Li4Ti5O12/Pt structure was prepared, and its electrical properties were studied. As for this thin film battery, the open circuit voltage was 1.9 V and the first discharge specific capacity was 34.7 μAh/cm2·μm at a current density of 5 μA/cm-2, indicating that is promising in all-solidstate thin film batteries.

scholarly journals Calcium Current Activated by Depletion of Calcium Stores in Xenopus Oocytes

1997 ◽  
Vol 109 (6) ◽  
pp. 703-715 ◽  
Author(s):  
Yong Yao ◽  
Roger Y. Tsien
Keyword(s):  
Xenopus Oocytes ◽  
Voltage Dependence ◽  
Calcium Stores ◽  
Kinase C ◽  
Electrode Voltage ◽  
Activation Mechanisms ◽  
Electrophysiological Characterization ◽  
Inwardly Rectifying ◽  
A Current

Ca2+ currents activated by depletion of Ca2+ stores in Xenopus oocytes were studied with a two-electrode voltage clamp. Buffering of cytosolic Ca2+ with EGTA and MeBAPTA abolished ICl(Ca) and unmasked a current in oocytes that was activated by InsP3 or ionomycin in minutes and by thapsigargin or the chelators themselves over hours. At −60 mV in 10 mM extracellular CaCl2, the current was typically around −90 or −160 nA in oocytes loaded with EGTA or MeBAPTA, respectively. This current was judged to be a Ca2+-selective current for the following reasons: (a) it was inwardly rectifying and reversed at membrane potentials usually more positive than +40 mV; (b) it was dependent on extracellular [CaCl2] with Km = 11.5 mM; (c) it was highly selective for Ca2+ against monovalent cations Na+ and K+, because replacing Na+ and K+ by N-methyl-d-glucammonium did not reduce the amplitude or voltage dependence of the current significantly; and (d) Ca2+, Sr2+, and Ba2+ currents had similar instantaneous conductances, but Sr2+ and Ba2+ currents appeared to inactivate more strongly than Ca2+. This Ca2+ current was blocked by metal ions with the following potency sequence: Mg2+ << Ni2+ ≈ Co2+ ≈ Mn2+ < Cd2+ << Zn2+ << La3+. It was also inhibited by niflumic acid, which is commonly used to block ICl(Ca). PMA partially inhibited the Ca2+ current, and this effect was mostly abolished by calphostin C, indicating that the Ca2+ current is sensitive to protein kinase C. These results are the first detailed electrophysiological characterization of depletion-activated Ca2+ current in nondialyzed cells. Because exogenous molecules and channels are easy to introduce into oocytes and the distortions in measuring ICl(Ca) can now be bypassed, oocytes are now a superior system in which to analyze the activation mechanisms of capacitative Ca2+ influx.

A study of the electrochemical behaviour of cobalt in aqueous H2CO3/HCO3–/CO32– solutions at pH 7–9

2004 ◽  
Vol 82 (5) ◽  
pp. 583-594 ◽  
Author(s):  
Stéphan Simard ◽  
Danick Gallant
Keyword(s):  
Open Circuit Potential ◽  
Competitive Adsorption ◽  
Carbonic Acid ◽  
Acid Corrosion ◽  
Electrochemical Behaviour ◽  
Open Circuit ◽  
Corrosion Process ◽  
Rotating Disc ◽  
Solution Interface ◽  
Potential Decay

The electrochemical behaviour of a cobalt rotating electrode in H2CO3/HCO3–/CO32– aqueous solutions was investigated in the pH region from 7 to 9. The effects of H2CO3/HCO3–/CO32– concentration, pH, and the presence of phosphates as inhibitors was explored using a rotating disc electrode at 1000 rpm. Some potentiodynamic experiments indicate that for pH 8.5 and higher, carbonate and bicarbonate species play a key role on the rate of electrooxidation of cobalt. For pH lower than 8.5, the electrochemical behaviour of cobalt changes drastically and very aggressive corrosion is observed. The involvement of carbonic acid must be considered in the corrosion process of cobalt in this pH region. The study of passive film potential decay under open circuit potential and galvanostatic reduction was performed on preanodized cobalt electrodes in solutions of various compositions. These experiments indicated the phenomena occurring at the electrode–solution interface during the corrosion process. A mechanism involving competitive adsorption of different species is suggested on the basis of the experimental evidence.Key words: cobalt, bicarbonate, phosphate, carbonic acid, corrosion.

HETEROINTERFACE PROPERTIES OF NOVEL HYBRID SOLAR CELLS CONSISTING OF TRANSPARENT CONDUCTIVE POLYMERS AND III-NITRIDE SEMICONDUCTOR

2010 ◽  
Vol 19 (04) ◽  
pp. 703-711 ◽  
Author(s):  
NOBUYUKI MATSUKI ◽  
YOSHITAKA NAKANO ◽  
YOSHIHIRO IROKAWA ◽  
MASATOMO SUMIYA
Keyword(s):  
Solar Cells ◽  
Schottky Contact ◽  
Conductive Polymer ◽  
Open Circuit ◽  
Semiconductor Layer ◽  
Clear Correlation ◽  
Hybrid Solar Cells ◽  
Specific Frequency ◽  
Rapid Drop

We have investigated the heterointerface properties of recently developed hybrid solar cells comprising a Schottky contact made of transparent conductive polymer (TCP) and an underlying GaN semiconductor layer. The heterointerface capacitance induced by the depletion layer under the TCP Schottky contact showed a rapid drop at a specific frequency. An intrinsic capacitance component that was derived from the capacitance–frequency (C–f) characteristics of the heterointerface showed clear correlation with the open circuit voltage. Hence, the C–f characterization using TCP Schottky contacts is indicative of the quality of the heterointerface.

All Solution-Based Fabrication of CIGS Solar Cell

2013 ◽  
Author(s):  
Robert L. Vittoe ◽  
Tung Ho ◽  
Sudhir Shrestha ◽  
Mangilal Agarwal ◽  
Kody Varahramyan
Keyword(s):  
Solar Cells ◽  
Solar Cell ◽  
Copper Chloride ◽  
Short Circuit ◽  
Spray Coating ◽  
Short Circuit Current ◽  
Open Circuit ◽  
Layer By Layer ◽  
Zinc Oxide Film ◽  
Indium Chloride

This paper presents fabrication of copper indium gallium di-selenide (CIGS) solar cells using all solution-based deposition processes. CIGS nanoparticles were synthesized through multi-step chemical process using copper chloride, indium chloride, gallium chloride, and selenium in oleyamine. CIGS thin films were constructed through layer-by-layer (LbL) self-assembly and spray-coating techniques. Chemical-bath-deposition and spray-coating methods were used for cadmium sulfide and zinc oxide film depositions, respectively. Initial thin film solar cell devices exhibited promising 0.3 mA short circuit current and 200 mV open circuit voltage. The solar cells fabricated through the all solution-based processes are cost-effective, thus, have potentials of providing a viable, renewable and sustainable energy source. The proposed processes can further be realized on flexible substrates, which may broaden the applications range for the solar cells.

Effect of operational parameters on cow dung mediated microbial fuel cell

2015 ◽  
Vol 12 (6) ◽  
pp. 541-550 ◽  
Author(s):  
Kiran Sethia ◽  
Alka Kaushik ◽  
S. K. Jadhav ◽  
Afaque Quraishi
Keyword(s):  
Rural Areas ◽  
Microbial Fuel Cells ◽  
Research Work ◽  
Open Circuit ◽  
Cow Dung ◽  
Operational Parameters ◽  
Bacterial Strains ◽  
New Approach ◽  
Ph Range ◽  
A Current

A new approach in the field of renewable energy is- the microbial fuel cells (MFCs). It is a technique to produce bioelectricity from available organic waste. It is helpful to fulfill the lighting requirements of rural areas. The aim of our research work is to construct twocompartment system and to study various parameters like performance of the different combination of electrodes, optimization of pH and temperature. In this study, using bacteria as biocatalyst, the naturally found cow dung was used to generate an open circuit voltage of 0.84 ± 0.010 V and a current of 3.51 ± 0.620 mA. Optimization of various parameters shows that among different temperature range, 37°C temperature gives the highest voltage production of 0.84 ± 0.091 V and current of 3.08 ± 0.512 mA. In case of pH there are not any significant changes were found when pH range is changed. Although, pH 4.0 is found to be more efficient as it produces voltage of 0.90 ± 0.045 V and current of 4.85 ± 0.587 mA. Furthermore, three electrogenic bacterial strains were isolated and studied for their electrogenic properties individually and among them CDB-3 was found best in their performance.

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