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

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.

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

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.721.95 ◽

2013 ◽

Vol 721 ◽

pp. 95-104 ◽

Cited By ~ 4

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.

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Study on Corrosion of Macroporous Silicon in Sodium Hydroxide Solution by Electrochemical Methods and Scanning Electron Microscopy

International Journal of Corrosion ◽

10.1155/2015/375489 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7

Author(s):

Chuan Lai ◽

Zhen Xiang ◽

Changlu Liu ◽

Chaoju Zhu ◽

Hui Wang ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Linear Polarization ◽

Polarization Resistance ◽

Corrosion Current Density ◽

Corrosion Current ◽

Open Circuit ◽

Macroporous Silicon ◽

Linear Polarization Resistance ◽

Scanning Electron

The fabricated macroporous silicon with a porosity of 26.33% corrosion in NaOH solution was systemically investigated by open circuit potential measurements, linear polarization measurements, potentiodynamic polarization measurements, and scanning electron microscopy, respectively. Results show that the potential open circuit and linear polarization resistance decreases with the NaOH concentration increasing. The corrosion potential shifts significantly to more negative potentials and corrosion current density increases with NaOH concentration increasing. Adding ethanol to 1.0 M NaOH can lead to the linear polarization resistance decrease, corrosion potentials shift in the positive direction, and corrosion current density increase. In addition, the scanning electron microscopy images demonstrate that the macroporous silicon samples are seriously damaged by 1.0 M NaOH and 1.0 M NaOH/EtOH (30%).

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Understanding the Nature of the Manganese Hot Dip Phosphatizing Process of Steel

Journal of the Mexican Chemical Society ◽

10.29356/jmcs.v57i4.197 ◽

2017 ◽

Vol 57 (4) ◽

Cited By ~ 1

Author(s):

Gabriela Alvarado-Macías ◽

Juan Carlos Fuentes-Aceituno ◽

Armando Salinas-Rodríguez ◽

Francisco Javier Rodríguez-Varela

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Phosphoric Acid ◽

Species Distribution ◽

Open Circuit Potential ◽

Open Circuit ◽

The Other ◽

Energy Dispersive ◽

X Ray ◽

Scanning Electron

In this work, the phosphatizing process of steel is investigated using open circuit potential and Tafel curves as well as scanning electron microscopy and energy dispersive X-ray spectroscopy. The results reveal that a pH of 2.57 in the phosphatizing solution promotes the dissociation of phosphoric acid which assists the formation of the manganese tertiary salt (Mn3(PO4)2), which is deposited on the substrate. It was also observed that an increase in the temperature from 25 to 90°C and the presence of HNO3 as catalyst enhances the manganese phosphatizing kinetics. On the other hand, the generation of iron phosphates and oxides is predominant at a pH of 1 and 90°C. These observations are supported by species distribution and Pourbaix thermodynamic diagrams.

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Fabrication and Photoresponse of Self-Organized TiO2 Mesoporous by Alternative Voltage Condition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.626.580 ◽

2012 ◽

Vol 626 ◽

pp. 580-583

Author(s):

Pacharee Krongkitsiri ◽

Udom Tipparach

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Oxalic Acid ◽

Open Circuit Potential ◽

Pure Titanium ◽

Open Circuit ◽

Self Organized ◽

Anodization Method ◽

Scanning Electron

Mesoporous of TiO2electrodes (MOTE) were fabricated on pure titanium sheets in aqueous based electrolytes that consist of NaSO4NH4F and Oxalic acid by an anodization method with alternative voltage condition. Morphology of MOTE was characterized by scanning electron microscopy. The characteristic photoresponse in 0.1 M Na2SO4on the MOTE was investigated. The MOTE shows an excellent photoresponse property that is significant at low open-circuit potential.

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Application of polypyrrole nanowires for the development of a tyrosinase biosensor

Chemical Papers ◽

10.1515/chempap-2015-0114 ◽

2015 ◽

Vol 69 (8) ◽

Cited By ~ 4

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.

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In-Situ Scanning Electron-Microscopy Interrogation on Open-Circuit Release of Toxic Ni2+ Ion from Ni-Containing Carbon Nanomaterials and Nickel-Hexacyanoferrate formation in Physiological pH and Its Thiol-Electrocatalysis Relevance

Electrochimica Acta ◽

10.1016/j.electacta.2021.139806 ◽

2021 ◽

pp. 139806

Author(s):

Sairaman Saikrithika ◽

Anlin Shaju ◽

Bose Dinesh ◽

Annamalai Senthil Kumar

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Carbon Nanomaterials ◽

Open Circuit ◽

Nickel Hexacyanoferrate ◽

Scanning Electron

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

MRS Proceedings ◽

10.1557/proc-634-b3.11.1 ◽

2000 ◽

Vol 634 ◽

Cited By ~ 12

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.

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The Electrochemical Behavior of Electrolytic Tinplate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.399-401.126 ◽

2011 ◽

Vol 399-401 ◽

pp. 126-129 ◽

Cited By ~ 1

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.

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Adhesion Improvement of Nickel Electrodeposited on Aluminum Alloy 7075 by Modified Single Zincating Process

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.694.143 ◽

2016 ◽

Vol 694 ◽

pp. 143-150 ◽

Cited By ~ 1

Author(s):

Intan Sharhida Othman

Keyword(s):

Electron Microscopy ◽

Open Circuit Potential ◽

Open Circuit ◽

Transition Curve ◽

Dense Layer ◽

X Rays ◽

Energy Dispersive Analysis ◽

Electrodeposited Nickel ◽

Aluminum Alloy 7075 ◽

Scanning Electron

The time-transition curve of open circuit potential (Eoc) during the single zincating process of aluminium alloy 7075 (AA7075) was recorded. Then, a suitable single zincating duration was selected from the Eoc slope, in order to get the optimum zincating duration. The evolution of surface morphology and composition of AA7075 substrate at various single zincating durations were characterized by scanning electron microscopy (SEM) and energy dispersive analysis of x- rays (EDX). The coating adhesions of single zincated samples produced at various durations were investigated using a scratch tester. SEM results showed that the substrates produced at a longer zincating duration were fully covered by a dense layer of zinc particles. The adhesion of the electrodeposited nickel on single zincated samples produced at longer zincating duration was higher than the conventional single zincating process. This morphology has contributed to the improvement of coating adhesion.

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

Modern Physics Letters B ◽

10.1142/s0217984989000844 ◽

1989 ◽

Vol 03 (06) ◽

pp. 525-535 ◽

Cited By ~ 20

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.

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