Effect of Indium Addition on the Electrochemical Behavior of Zinc Electrodes in Concentrated Alkaline Solutions

2013 ◽  
Vol 721 ◽  
pp. 95-104 ◽  
Author(s):  
Hong Xia Liang ◽  
Zhi Lin Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electrochemical Behavior ◽  
Constant Current ◽  
Alkaline Solutions ◽  
Zinc Electrode ◽  
Pure Zinc ◽  
Current Densities ◽  
Potentiostatic Polarization ◽  
Scanning Electron

The electrochemical behavior of zinc electrode with indium addition in 35%KOH(or saturated with ZnO) solutions has been investigated systematically by electrochemical methods including linear polarization, potentiostatic polarization, potentiodynamic anodic polarization, potential-time measurements at a constant current density, combining the observations of scanning electron microscopy (SEM). It is indicated that the indium addition makes the corrosion potential of Zn shifted positively and its corrosion current increased. Galvanostatic results showed that the addition of indium shortened the passivation time, indicating indium is an active element to the electrochemical performance of zinc alloy electrode. The potentiostatic polarization curves of the pure zinc plate and zinc-indium alloy electrodes in a 35%KOH solution saturated with ZnO indicated that the addition of indium improved the cathodic polarization of alloy electrodes and the deposition overpotential,mean while it depressed the deposition morphology of zinc on the electrode and accelerated the dendrite growth. Scanning electron microscopy images showed that the addition of indium aggravated the corrosion of zinc electrode which may be responsible for the increased tendency to passivation at high current densities. It has been found that at low current densities the reaction kinetics may be increased by indium addition , which is agreement with the discharging test of actual alkaline batteries.

Effect of Bi Addition on the Electrochemical Behavior of Zinc Electrodes in Concentrated Alkaline Solutions

2013 ◽  
Vol 805-806 ◽  
pp. 1240-1249
Author(s):  
Hong Xia Liang ◽  
Fu Rong Li ◽  
Zhi Lin Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Linear Polarization ◽  
Electrochemical Behavior ◽  
Open Circuit Potential ◽  
Open Circuit ◽  
Exchange Current ◽  
Zinc Electrode ◽  
Current Densities ◽  
Scanning Electron

The electrochemical behavior of zinc electrode with bismuth addition in 35%KOH solutions has been investigated systematically by electrochemical methods including linear polarization, potentiostatic polarization, potential-time measurements at a constant current density, combining the observations of scanning electron microscopy (SEM). Linear polarization results showed that the open circuit potential shifted positively with increasing bismuth content, which is explained based on the gassing data and change in the exchange current of the zinc electrode. Addition of bismuth increased the exchange current of zinc reaction and caused an increase in the measured open circuit potential. Galvanostatic results showed that the addition of bismuth shortened the passivation time. Scanning electron microscopy images showed that the addition of bismuth aggravated the corrosion of zinc electrode which may be responsible for the increased tendency to passivation at high current densities. It has been found that at low current densities the reaction kinetics may be increased by addition of Bi, which is general agreement with the discharging test of actual alkaline batteries.

Application of polypyrrole nanowires for the development of a tyrosinase biosensor

2015 ◽  
Vol 69 (8) ◽  
Author(s):  
Jolanta Kochana ◽  
Katarzyna Hnida ◽  
Grzegorz Sulka ◽  
Paweł Knihnicki ◽  
Joanna Kozak ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Matrix Composite ◽  
Electrochemical Behavior ◽  
Structural Component ◽  
Operational Stability ◽  
Amperometric Biosensor ◽  
Polypyrrole Nanowires ◽  
Tyrosinase Biosensor ◽  
Scanning Electron

AbstractPolypyrrole nanowires (PPyNWs) were fabricated and examined as a structural component of amperometric biosensor matrix. An enzyme, tyrosinase (TYR), was immobilized onto PPyNWs using glutaraldehyde (GA). Matrix composite morphology was investigated using scanning electron microscopy. Electrochemical behavior of the prepared PPyNWs/GA/TYR biosensor towards catechol was studied and the assessment of its analytical characteristics was carried out taking into account linear range, sensitivity, repeatability, reproducibility and operational stability.

Anodizing of Pure Magnesium in Sodium Hydroxide Electrolyte Solution

2020 ◽  
Vol 405 ◽  
pp. 440-444
Author(s):  
Michal Páleníček ◽  
Martin Papula ◽  
Michaela Remešová ◽  
David Jech ◽  
Ivana Ročňáková ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Digital Image Analysis ◽  
Electrochemical Process ◽  
Pure Magnesium ◽  
Constant Current ◽  
Constant Voltage ◽  
Corrosion Resistant ◽  
Anodic Layer ◽  
Scanning Electron

Anodizing is an electrochemical process to produced anodic coatings for improving magnesium (Mg) properties such as corrosion-resistant. In this study, anodizing of pure magnesium in 1 M NaOH electrolyte for 1800 s and at 21 °C and different constant current or voltage was investigated. The effect of voltage and current on morphology and thickness of the resulting anodic layers was evaluated by scanning electron microscopy (SEM) equipped with EDX analyser. The thickness of the produced layers was determined to utilize digital image analysis. The results showed that using lower current of 0.08 A non-compact anodic layer was produced. When a higher current of 0.2 and 0.5 A was used compact and thicker anodic layers were produced compare to lower current of 0.08 A. The anodic layer produced at a constant voltage of 20 V was rougher, thicker and contained microcracks compare to anodic layers formed at constant voltage of 12 V and at constant current (0.2 and 0.5 A).

The Effect of Deposition Parameters on Tensile Properties of Pulse-Plated Nanocrystalline Nickel

2000 ◽  
Vol 634 ◽  
Author(s):  
K. L. Morgan ◽  
Z. Ahmed ◽  
F. Ebrahimi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Grain Size ◽  
Tensile Properties ◽  
Nanocrystalline Nickel ◽  
Cathodic Current ◽  
Deposition Parameters ◽  
Current Densities ◽  
D 12 ◽  
Scanning Electron

ABSTRACTThe microstructure and tensile properties were investigated for pulse-plated nanocrystalline nickel electrodeposits prepared from an additive-free sulfamate-based solution. Square-wave cathodic current densities were varied from 25 to 75 mA/cm2. The samples deposited at 25 mA/cm2 showed the smallest grain size (d ∼ 12 nm), and the grain size was found to increase with increasing current densities. The grain size of the electrodeposits ranged from approximately 27 to 12 nm. Tensile results indicated that the yield strength of the specimens increased with decreasing grain size. Scanning electron microscopy revealed that all electrodeposits fractured through a ductile mechanism.

The Electrochemical Behavior of Electrolytic Tinplate

2011 ◽  
Vol 399-401 ◽  
pp. 126-129 ◽  
Author(s):  
Hui Ping Bai ◽  
Yuan Qiang Tu ◽  
Chang Fu Liu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Corrosion Resistance ◽  
Electrochemical Behavior ◽  
Alloy Layer ◽  
Electrochemical Methods ◽  
Scanning Electron

The electrochemical behavior of electrolytic tinplates was studied and analyzed by means of electrochemical methods together with tin quantity test and scanning electron microscopy (SEM). The results indicated that the properties of the Sn-Fe alloy layer determined the electrochemical behavior of electrolytic tinplates. The electrolytic tinplate possessed higher corrosion resistance if the Sn-Fe alloy layer was thicker and more compact.

HIGH-FIELD AND MICROSTRUCTURE STUDIES OF SUPERCONDUCTING nYBa2Cu3Oy:AgO COMPOSITES

1989 ◽  
Vol 03 (06) ◽  
pp. 525-535 ◽  
Author(s):  
C.Y. HUANG ◽  
H.H. TAI ◽  
M.K. WU
Keyword(s):  
Magnetic Field ◽  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Field ◽  
Polarized Light ◽  
Critical Fields ◽  
Strong Pinning ◽  
Current Densities ◽  
Very High ◽  
Scanning Electron

We have measured the resistance of superconducting n YBa 2 Cu 3 O y: AgO (n=2,3,4, and 5) composites above 77 K for magnetic field up to 20 T. The data reveal that the resistance is zero even at 80 K and 20 T. The temperature dependence of the critical field near T c (91.6 K) is very strong, and critical fields at 0 K are thus expected to be very high. Our results of scanning electron microscopy and polarized light microscopy have shown that the presence of silver results in the growth of very large grains (~0.5 mm) with silver dispersed in the grains, giving rise to strong pinning and, hence, large superconducting critical current densities.

scholarly journals Reversible Deposition and Dissolution of Magnesium from Imidazolium-Based Ionic Liquids

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
QingSong Zhao ◽  
Yanna NuLi ◽  
Tuerxun Nasiman ◽  
Jun Yang ◽  
JiuLin Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Ionic Liquids ◽  
Room Temperature ◽  
Constant Current ◽  
Imidazolium Cation ◽  
Methyl Group ◽  
X Ray ◽  
Imidazolium Cations ◽  
Scanning Electron

The electrochemical performance of six imidazolium cation-based ionic liquids (ILs) containing 0.3 mol L-1Mg(CF3SO3)2as the electrolytes for magnesium deposition-dissolution was examined by cyclic voltammogramms and constant current discharge-charge techniques. Scanning electron microscopy and energy dispersive X-ray spectroscopy measurements were conducted to characterize the morphologies and components of the deposits. The cathodic satiability of imidazolium cations can be improved by increasing the length of alkyls at the 1-position and introducing methyl group at the 2-position of the imidazolium cations. A reversible magnesium deposition-dissolution can be achieved at room temperature. After adding appreciate amount of tetrahydrofuran (THF) organic solvent, the conductivity and the peak currents for Mg deposition and dissolution can be significantly improved. The potential polarization of deposition-dissolution process is decreased using Mg powder electrode.

scholarly journals ELECTROCHEMICAL PERFORMANCES AND CORROSION INHIBITION OF AA6061 IN TROPICAL SEAWATER

2017 ◽  
Vol 25 (2) ◽  
pp. 251-259
Author(s):  
R. Rosliza ◽  
H.B. Senin ◽  
W.B. Wan Nik
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electrochemical Impedance ◽  
Corrosion Current ◽  
Electrochemical Performances ◽  
Double Layer Capacitance ◽  
Sem Images ◽  
Corrosion Rates ◽  
Current Densities ◽  
Scanning Electron

The corrosion performances of AA6061 aluminum alloy in tropical seawater was investigated using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and their morphology was characterized by the scanning electron microscopy (SEM). The results showed that the presence of sodium benzoate as an inhibitor significantly decrease the corrosion current densities (i corr ), corrosion rates and double layer capacitance (C dl ), whilst increasing the polarization resistance (R p ). The scanning electron microscopy (SEM) images indicated that the mechanism of charge transfer and the formation of thin film have been taken place on the specimens. 

Pathogenesis of Human Hair Defects

1974 ◽  
Vol 32 ◽  
pp. 12-13
Author(s):  
P.S. Porter ◽  
T. Aoyagi ◽  
R. Matta
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Human Hair ◽  
Standard Techniques ◽  
Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

1977 ◽  
Vol 35 ◽  
pp. 638-639
Author(s):  
P.J. Dailey
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Salivary Glands ◽  
Secretory Vesicles ◽  
The Past ◽  
Transmission Electron ◽  
Means Of Transmission ◽  
Gromphadorhina Portentosa ◽  
Scanning Electron ◽  
Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

Sign in / Sign up

Export Citation Format

Share Document