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Full-Text Articles in Engineering

Fundamentals Of Electrochemical Impedance Spectroscopy For Macrohomogeneous Porous Electrodes, Xiang Li, Qiu-An Huang, Wei-Heng Li, Yu-Xuan Bai, Jia Wang, Yang Liu, Yu-Feng Zhao, Juan Wang, Jiu-Jun Zhang Oct 2021

Fundamentals Of Electrochemical Impedance Spectroscopy For Macrohomogeneous Porous Electrodes, Xiang Li, Qiu-An Huang, Wei-Heng Li, Yu-Xuan Bai, Jia Wang, Yang Liu, Yu-Feng Zhao, Juan Wang, Jiu-Jun Zhang

Journal of Electrochemistry

Electrochemical impedance spectroscopy (EIS) can be used to diagnose charge transfer reactions and mass transport in porous electrodes. The charge transfer reactions include interfacial charge accumulation and charge conduction as well as electrochemical reaction. In this paper, the complex phasor method is developed under the macrohomogeneous assumption to build an impedance model of porous electrodes for clarifying several vague expressions in the traditional approaches. The following researches are carried out: (1) Identifying characteristic parameters for the porous electrodes, including electrode electronic conductivity σ1, electrolyte ionic conductivity σ2, interface charge transfer conductivity gct, unit area …


Degradation And Thermal Characteristics Of Lini0.8Co0.15Al0.05O2/Graphite Lithium Ion Battery After Different State Of Charge Ranges Cycling, Cun Wang, Wei-Jiang Zhang, Teng-Fei He, Bo Lei, You-Jie Shi, Yao-Dong Zheng, Wei-Lin Luo, Fang-Ming Jiang Dec 2020

Degradation And Thermal Characteristics Of Lini0.8Co0.15Al0.05O2/Graphite Lithium Ion Battery After Different State Of Charge Ranges Cycling, Cun Wang, Wei-Jiang Zhang, Teng-Fei He, Bo Lei, You-Jie Shi, Yao-Dong Zheng, Wei-Lin Luo, Fang-Ming Jiang

Journal of Electrochemistry

The LiNi0.8Co0.15Al0.05O2 (NCA) cathode exhibits high energy density and large reversible capacity, which plays an essential role in the field of electric vehicles (EVs). However, low capacity retention and poor thermal stability limit its application. Few literatures are found for the capacity degradation mechanism of NCA/graphite batteries at home and abroad. The different state of charge (SOC) ranges cycle degradation behaviors of 18650-type NCA/graphite (2.4 Ah) battery were studied in this paper. The SOC ranges considered were 0% ~ 20% (low), 20% ~ 70% (medium), 70% ~ 100% (high), and 0% ~ 100% …


Fundamentals Of Distribution Of Relaxation Times For Electrochemical Impedance Spectroscopy, Jia Wang, Qiu-An Huang, Wei-Heng Li, Juan Wang, Quan-Chao Zhuang, Jiu-Jun Zhang Oct 2020

Fundamentals Of Distribution Of Relaxation Times For Electrochemical Impedance Spectroscopy, Jia Wang, Qiu-An Huang, Wei-Heng Li, Juan Wang, Quan-Chao Zhuang, Jiu-Jun Zhang

Journal of Electrochemistry

Electrochemical impedance spectroscopy (EIS) is a powerful electrochemical characterization technology, which has been widely used in the field of electrochemical energy, such as lithium-ion batteries, supercapacitors, fuel cells, etc. Distribution of relaxation time (DRT) is an EIS deconvolution technique which does not depend on the prior knowledge of the targeted research object. Furthermore, DRT can serve to separate and analyze physical and chemical processes which are highly overlapped in their EIS data. In order to encourage the application and popularization of DRT deconvolution technology, several core questions are addressed in this paper: (1) DRT deconvolution principle, implementation steps and important …


The Pilot Application Of Electrochemical Impedance Spectroscopy On Dynamic Proton Exchange Membrane Fuel Cell, Jian-Wei Guo, Jian-Long Wang Dec 2018

The Pilot Application Of Electrochemical Impedance Spectroscopy On Dynamic Proton Exchange Membrane Fuel Cell, Jian-Wei Guo, Jian-Long Wang

Journal of Electrochemistry

By analyzing Electrochemical Impedance Spectroscopy (EIS) in applications of dynamic proton exchange membrane fuel cell (PEMFC), bottlenecks which restrict EIS tool development have been pointed out in this paper. Though the high-frequency resistance in EIS is largely accepted as cell inner-resistance, this can only be applied for cell with low current. The low-frequency resistance is difficult to be realized due to its relation with mass transfer. Furthermore, the improved Randles equivalent circuits are built up preliminarily, thus, penetrating into studies for mass transfer reaction, cell operation/degeneration, and high temperature fuel cell. Inspiringly, EIS is becoming an analyzing tool for stack …


Intrinsic Kinetic Properties Of Ternary Material For Lithium Ion Batteries Assessed By Single Particle Microelectrode, Yi-Min Wei Feb 2018

Intrinsic Kinetic Properties Of Ternary Material For Lithium Ion Batteries Assessed By Single Particle Microelectrode, Yi-Min Wei

Journal of Electrochemistry

Electrochemical performances such as capacity, rate, cycle and thermal stability of the nickel (Ni), cobalt (Co) and manganese (Mn) ternary cathode material, LiNixCoyMnzO2 (x + y + z = 1), are significantly influenced by the proportion of Ni, Co, and Mn elements. To obtain higher specific capacity, LiNi0.6Co0.2Mn 0.2O2 (NCM622) and LiNi0.8Co0.1Mn0.1O2 (NCM811) with high amounts of Ni element were employed for the lithium ion batteries. By now, many studies have been focusing on the thermal and cycling stabilities of …


Kinetics And Mechanism Toward Electrochemical Reductions Of Sodium Bromide And Methanol Over Iron Electrodes, Qun Liao, Shu-Feng Zhang, Wen-Hua Leng Dec 2017

Kinetics And Mechanism Toward Electrochemical Reductions Of Sodium Bromide And Methanol Over Iron Electrodes, Qun Liao, Shu-Feng Zhang, Wen-Hua Leng

Journal of Electrochemistry

It is of technological value and scientific interest to the electro-synthesis of ferrocene, conversion of carbon dioxide (CO2) and organic electro-synthesis in non-aqueous solutions by investigating the kinetics and mechanism toward electrochemical reductions of sodium bromide (NaBr) and methanol over iron electrodes. However, few reports in the related researches are available. In this article, the kinetics and mechanism toward electrochemical reductions of NaBr and methanol over iron electrodes were examined in detail by carrying out the polarization curve and electrochemical impedance spectroscopic measurements. The results showed that methanol was the reactant, while Na+ ions were functioned only …


The Study Of Dynamical Electrochemical Impedance Spectroscopy For Oxygen Reduction Reaction On Pt/C Catalyst, Kun-Ming Shi, Jian-Wei Guo, Jia Wang Oct 2016

The Study Of Dynamical Electrochemical Impedance Spectroscopy For Oxygen Reduction Reaction On Pt/C Catalyst, Kun-Ming Shi, Jian-Wei Guo, Jia Wang

Journal of Electrochemistry

With joint techniques of rotating disc electrode(RDE) and electrochemical impedance spectroscopy(EIS), and further establishment on equivalent circuit model, this paper studied oxygen reduction reaction(ORR) on commercial Pt/C catalyst in acid medium. Our results found that the dynamical interface on Pt/C consists of two independent processes: 1) the PtO reduction from Pt surface, 2) the new PtO formation from ORR, thus providing key clues for catalyst stability and activity. This also implied that the dynamical interface facilitates reconstruction for porous electrode, and matches with mass transfer. One important issue is discovered that at high overpotential, the high reaction rate for ORR …


Fabrication And Impedance Performance Of Gradient Lani0.6Fe0.4O3-δ-Gd0.2Ce0.8O2 Composite Cathodes For Intermediate Temperature Solid Oxide Fuel Cell, Yang Li, Bo Huang, Meng Yuan, Zhi-Qiu Zhang, Zong-Yao Liu, Xu-Chen Tang, Xin-Jian Zhu Feb 2014

Fabrication And Impedance Performance Of Gradient Lani0.6Fe0.4O3-δ-Gd0.2Ce0.8O2 Composite Cathodes For Intermediate Temperature Solid Oxide Fuel Cell, Yang Li, Bo Huang, Meng Yuan, Zhi-Qiu Zhang, Zong-Yao Liu, Xu-Chen Tang, Xin-Jian Zhu

Journal of Electrochemistry

A LNF-GDC composite cathode with a gradual change in the composition between ScSZ electrolyte and LNF cathode was fabricated to reduce the cathode polarization resistance (Rp). The gradual change in composition between ScSZ electrolyte and LNF cathode shows the decreases in the charge transfer resistance (Rct) and gas phase diffusion resistance (Rd). The results revealed that the Rp value, measuring 0.452 Ω·cm2 at 750 °C, was the lowest for LNF-GDC composite cathodes with three layers and gradient changes in composition between ScSZ and LNF (Cathode C),, whereas the Rp value of 70%LNF-30%GDC composite …


An Investigation Of Photocatalytic Degradation Reactions Of Pollutants By Combination Of (Photo)Electrochemical Measurements, Wen-Hua Leng, Hong-Qiao Zhu Oct 2013

An Investigation Of Photocatalytic Degradation Reactions Of Pollutants By Combination Of (Photo)Electrochemical Measurements, Wen-Hua Leng, Hong-Qiao Zhu

Journal of Electrochemistry

Semiconductor photocatalysis plays a critical role in the environment protection and future energy development. (Photo)electrochemical measurements are powerful tools for studying the kinetics and mechanism of photocatalytic reactions, since photo-carriers, as reactants of photocatalytic reactions, are involved in the interfacial transfer and recombination of semiconductor/electrolyte interface. This review describes the part of our recent results regarding aqueous photocatalytic decontamination obtained by these methods, and the focus of future work in this field is suggested.


Fabrication And Performance Of Lani0.6Fe0.4O3-δ Cathode Modified By Coating With Gd0.2Ce0.8O2 For Intermediate Temperature Solid Oxide Fuel Cell, Rui-Xuan Ren, Bo Huang, Xin-Jian Zhu, Yi-Xing Hu, Xiao-Yi Ding, Zong-Yao Liu, Ye-Bin Liu Jun 2013

Fabrication And Performance Of Lani0.6Fe0.4O3-δ Cathode Modified By Coating With Gd0.2Ce0.8O2 For Intermediate Temperature Solid Oxide Fuel Cell, Rui-Xuan Ren, Bo Huang, Xin-Jian Zhu, Yi-Xing Hu, Xiao-Yi Ding, Zong-Yao Liu, Ye-Bin Liu

Journal of Electrochemistry

The symmetric cell of LaNi0.6Fe0.4O3-δ/Sc0.1Zr0.9O1.95/LaNi0.6Fe0.4O 3-δ was fabricated with screen printing method. A LaNi0.6Fe0.4O3-δ (LNF) cathode was modified by coating with nano-sized gadolinium-doped ceria (GDC, Gd0.2Ce0.8O2) prepared using a simple combustion process within the pores of the cathode. According to the electrochemical impedance spectra (EIS), the polarization resistance of the pure LNF was 0.70 W·cm2 at 750 ºC, while 0.13 W·cm2 for the 21.3% GDC (by mass)-coated LNF …


A Comparative Study Of Charge-Discharge Behaviors Of Α-Pbo2 And Β-Pbo2 Cathodes, Cong-Ying Cui, Xue-Mei Ma, De-Long Kong, Hou-Yi Ma Feb 2013

A Comparative Study Of Charge-Discharge Behaviors Of Α-Pbo2 And Β-Pbo2 Cathodes, Cong-Ying Cui, Xue-Mei Ma, De-Long Kong, Hou-Yi Ma

Journal of Electrochemistry

The α-PbO2 and β-PbO2 powders were prepared using simple chemical synthetic methods, and their crystalline structures and surface morphologies were characterized with X-ray powder diffraction spectroscopy and scanning electron microscopy. Using the as-synthesized α-PbO2 and β-PbO2 powders as positive active materials, the electrochemical performance of the two PbO2 materials was investigated by means of cyclic voltammetry, galvanostatic charge-discharge tests, and electrochemical impedance spectroscopy. The results indicate that the discharge capacity of α-PbO2 electrode is larger than that of β-PbO2; moreover, the composite electrodes made by α-PbO2 and β-PbO2 mixtures with different proportions are favorable for enhancing the charge-discharge cycle performance …


Comments On Internal Alternating Current Resistance Test Standard And Methods Of Lithium-Ion Batteries, Ya-Li Zhang, Sen Xin, Yu-Guo Guo, Li-Jun Wan Jun 2012

Comments On Internal Alternating Current Resistance Test Standard And Methods Of Lithium-Ion Batteries, Ya-Li Zhang, Sen Xin, Yu-Guo Guo, Li-Jun Wan

Journal of Electrochemistry

The sustainable development of energy and environment is one of the most influential issues of this century. Batteries, especially secondary batteries are important for powering out daily life. However, in many practical applications, such as in electric vehicles and hybrid electric vehicles, batteries should be used in packs and the performance consistency of each battery in the pack should be taken into consideration. As one of the performance parameters being used to characterize the battery consistency, internal resistance is of great importance to the industrial fabrication and the use of batteries. Currently, internal resistance tests of secondary batteries, such as …


Electrochemical Detection For The Corrosion Of Reinforcing Steel In Concrete During Immersion And Drying Cycles, Bing-Li Jia, Fa-He Cao, An-Na Chen, Jian-Qing Zhang Nov 2010

Electrochemical Detection For The Corrosion Of Reinforcing Steel In Concrete During Immersion And Drying Cycles, Bing-Li Jia, Fa-He Cao, An-Na Chen, Jian-Qing Zhang

Journal of Electrochemistry

The corrosion behavior of reinforcing steel in concrete under dry-wet cycle condition has been studied by electrochemical noise(EN) compared with the electrochemical impedance spectroscopy(EIS),SEM micrographs and EDS.The statistical method has been employed to analyze the EN data of reinforcing steel in concrete,which revealed three different corrosion stages of reinforcing steel in concrete,including the dissolution of the passive film,the active corrosion and the cumulation of corrosion product.The wavelet transform has also been employed,which indicated that steel in concrete with pH 1 is associated with uniform corrosion,while steel in concrete with pH 3 and pH 7 are associated with localized corrosion,such as …


Preparation And Electrochemical Performance Of Three-Dimensional Porous Snco Alloy Electrode, Lian-Jie Xue, Ling Huang, Fu-Sheng Ke, Guo-Zhen Wei, Xiao-Mei Zheng, Jun-Tao Li, Xiao-Yong Fan, Shi-Gang Sun May 2010

Preparation And Electrochemical Performance Of Three-Dimensional Porous Snco Alloy Electrode, Lian-Jie Xue, Ling Huang, Fu-Sheng Ke, Guo-Zhen Wei, Xiao-Mei Zheng, Jun-Tao Li, Xiao-Yong Fan, Shi-Gang Sun

Journal of Electrochemistry

Three-dimensional porous Cu film was prepared by electroless plating,and used as a current collector for preparation of three-dimensional structured SnCo alloy electrode,which was mainly prepared by an electrodeposition method,and composed of pure Sn and CoSn2 phases. Electrochemical experimental results show that three-dimensional structured SnCo alloy electrode exhibits much better cycleability than planar SnCo alloy electrode,with first discharge capacity and charge capacity of 636. 3 and 528. 7 mAh·g-1,respectively. After 70th cycling,capacity retention is 83. 1% with 529. 5 mAh·g-1. The lithiation process during first discharge was investigated by electrochemical impedance spectroscopy


Direct Electrochemistry Of Hemoglobin On The Electrode Modified With Ddab And Swcnt, Wen-Jing Hou, Lin Zhou, Xia-Qin Wu, Hong-Xia Zhang, Wen Xie, Liu Yang, Zhong-Qing Lu Aug 2008

Direct Electrochemistry Of Hemoglobin On The Electrode Modified With Ddab And Swcnt, Wen-Jing Hou, Lin Zhou, Xia-Qin Wu, Hong-Xia Zhang, Wen Xie, Liu Yang, Zhong-Qing Lu

Journal of Electrochemistry

Hemoglobin(Hb) was immobilized onto the surface of glassy carbon electrode with the single-wall carbon nanotubes and surfactant didodecyldimethylamonium bromide(DDAB) modified previously and its electrochemical behaviors have been investigated by cyclic voltammetry.A pair of well-defined redox peaks has been obtained.Cyclic voltammetry and electrochemical impedance spectroscopy(EIS) were also used to study on the effect of different concentration of SWCNT in DDAB.The result shows that the 1 mg/mL is the best choice.The dependence of E0' on solution pH with the slope of 39 mV/pH,indicated that redox of the Hb is a one electron reaction with two protons transfer.The results also showed that the …


Corrosion Inhibition Of Self-Assembled Films On Iron By Electrochemical Impedance Spectroscopy, Yuan-Yuan Feng, Shen-Hao Chen, Juan-Juan Zhou, Wen-Juan Guo Aug 2008

Corrosion Inhibition Of Self-Assembled Films On Iron By Electrochemical Impedance Spectroscopy, Yuan-Yuan Feng, Shen-Hao Chen, Juan-Juan Zhou, Wen-Juan Guo

Journal of Electrochemistry

The self-assembled films of tetradecylamine were formed on iron surface,and the inhibition ability of which for iron corrosion in 0.5 mol/L H2SO4 solutions was studied by electrochemical impedance spectroscopy technique.Results indicated that longer immersion time would result in stronger inhibition ability of the films.The maximal inhibition efficiency(IE) of the tetradecylamine films was 68.7%.When the tetradecylamine films were modified by dodecylthiol,the mixed films became denser and more stable,thus the inhibition ability increased remarkably.The η of the mixed films increased to 78.2%.


Study On Electrochemical Impedance Spectroscopy Of Carbon Steel Eroded In Methyldiethanolamine Solution, Dong-Ping Wei, Rong-Zong Hu, Dan-Mei Pan, Wei-Xiong Huang, Rui Dong Nov 2007

Study On Electrochemical Impedance Spectroscopy Of Carbon Steel Eroded In Methyldiethanolamine Solution, Dong-Ping Wei, Rong-Zong Hu, Dan-Mei Pan, Wei-Xiong Huang, Rui Dong

Journal of Electrochemistry

Corrosion behavior of carbon steel in methyldiethanolamine(MDEA) solution was investigated by Electrochemical Impedance Spectroscopy(EIS).The results were showed that the corrosion rate of carbon steel in solution containing dissolved oxygen is higher than that in solution removed of dissolved oxygen before cathodic activation.They were reversed after cathodic activation.The corrosion rate is increased at first and then decreased when the concentration of MDEA is increased in the blank solutions.In the simulated solutions containing quantities of!heat-stable salts(HSS),the corrosion rate is decreased monotonously with increase of the MDEA concentration.As anodic polarization potential is increased,the EIS of carbon steel in HSS simulated solution showed characteristics …


Effects Of Direct Current Bias Potentials On Lipid Membranes Forming On A Glassy Carbon Electrode, Yu-Hui Li, Hong-Wei Zhang, Gui-Lan Song, Zhan-Jun Zhang, Sheng-Min Cai Feb 2007

Effects Of Direct Current Bias Potentials On Lipid Membranes Forming On A Glassy Carbon Electrode, Yu-Hui Li, Hong-Wei Zhang, Gui-Lan Song, Zhan-Jun Zhang, Sheng-Min Cai

Journal of Electrochemistry

The effects of direct current(DC) bias voltage on the structure of lipid membranes forming on a glassy carbon electrode(GCE) was investigated by cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS).The experiment showed that the lipid membranes can be formed with either positive or negative bias potential exerted.When bias voltage was exerted,bilayer lipid membranes tended to form due to the electrostatic interaction between the superficial positive charges on the polarized electrode and the negative charged part of PC.When the positive bias voltage overrun the range,the lacunas on s-BLMs would increase,and the BLMs would be broken.A proper equivalent circuit was nonlinearly fitted,based on the …


Fabrication And Performance Of Ni-Scsz Cermet Anode Modified By Coating With Gd_(0.2)Ce_(0.8)O_2 For A Sofc, Ren-Zhu Liu, Bo Huang, Xiao-Feng Ye, Shao-Rong Wang, Jia-Di Cao, Huai-Wen Nie, Ting-Lian Wen Feb 2007

Fabrication And Performance Of Ni-Scsz Cermet Anode Modified By Coating With Gd_(0.2)Ce_(0.8)O_2 For A Sofc, Ren-Zhu Liu, Bo Huang, Xiao-Feng Ye, Shao-Rong Wang, Jia-Di Cao, Huai-Wen Nie, Ting-Lian Wen

Journal of Electrochemistry

A Ni-scandia-stabilized zirconia(Ni-ScSZ) cermet anode modified by coating with nano-sized gadolinium-doped ceria(GDC,Gd0.2Ce0.8O2) was prepared using a simple combustion process for the solid oxide fuel cell(SOFC) running on methane fuel.X-ray diffraction(XRD) and scanning electron microscopy(SEM) indicated that the surface of Ni-ScSZ was coated by nano-sized GDC particles(<100nm).Single cell testing showed that the 2.0%(by mass) GDC-coated Ni-ScSZ anode had better performance.The highest power densities of the cell with this anode were 825 and 848mW/cm2 at 850℃ in humidified hydrogen and methane,respectively,whereas the corresponding values were 584 and 586mW/cm2 for the cell with Ni-ScSZ anode.Electrochemical impedance spectra(EIS) illustrated that the cell with Ni-ScSZ anode exhibited far greater impedances than the cell with 2.0%(by mass) GDC-coated Ni-ScSZ anode.Then the short-term stability for the cells with the Ni-ScSZ and 2.0%(by mass) GDC-coated Ni-ScSZ anodes in 97%CH4/3%H2O at 700℃ was checked over a relative long period of operation.No significant degradation in performance has been observed after 84 h of cell testing when 2.0%(by mass) GDC-coated Ni-ScSZ anode was exposed to 97%CH4/3%H2O at 700 ℃.Very little carbon was detected on the anodes,suggesting that carbon deposition was limited during cell operation.


Mechanism Of Self Discharge Performance Improvement In The Ni-Mh Batteries With Naoh Electrolyte, Xiao-Feng Li Feb 2006

Mechanism Of Self Discharge Performance Improvement In The Ni-Mh Batteries With Naoh Electrolyte, Xiao-Feng Li

Journal of Electrochemistry

The self-discharge performance and charge efficiency at 60 ℃ for Ni-MH battery can be markedly enhanced by using NaOH electrolyte instead of KOH electrolyte.Both the results of electrochemical impedance spectroscopy and cyclic voltammetry tests indicate that the separation of H_2 from the negative electrode may be partly blocked in the former because of the change of the adsorption/desorption behavior of H on the surface of the negative electrode,thus results in an improvement of self-discharge performance of the battery.


Adsorption Of Polyaspartic Acid From Sulphur Acid Solution On Carbon Steel And Its Corrosion Inhibition, Rong-Jing Cui, Ning Gu, Chun-Mei Li Aug 2005

Adsorption Of Polyaspartic Acid From Sulphur Acid Solution On Carbon Steel And Its Corrosion Inhibition, Rong-Jing Cui, Ning Gu, Chun-Mei Li

Journal of Electrochemistry

The role of Polyaspartic acid in the corrosion inhibition of 45~(#) carbon steel in sulphuric acid solution has been investigated by polarization curve andelectrochemical impedance spectroscopy (EIS). The influences of the concentration and the temperature of PASP on the corrosion inhibition efficiency were determined. The results indicated that the PASP as the corrosion inhibitor mainly inhibitated the anode; within the experiment temperature, the inhibitor efficiency decreased with the raising of the temperature and PASP had a good inhibiting performance at 10℃, the corrosion inhibition efficiency of PASP for carbon steel increased with the increase of the concentration of PASP when …


The Fabrication And Electrochemical Studies On Carbon Nanotube Array Electrodes, Quan-Yong Gao, Jing Zhang, Yangyong Yangyong Feb 2005

The Fabrication And Electrochemical Studies On Carbon Nanotube Array Electrodes, Quan-Yong Gao, Jing Zhang, Yangyong Yangyong

Journal of Electrochemistry

An improved technique for fabrication of carbon nanotube array electrodes has been proposed in this work. Firstly, carbon nanotubes (CNs) array electrodes were prepared by combsination of Chemical Vapor Decomposition (CVD) method and sputtering techniques in anodized aluminum oxide (AAO) membrane. The CNs/AAO was immersed into HF solution to remove the barrier layer. Controlling the immersing time, the CNs array electrodes with different length contacted with electrolyte can be prepared. The morphology of CNs array electrodes was observed by SEM. The electrochemical properties of CNs array electrodes were investigated by cyclic voltammetry and electrochemical impedance spectroscopy. Cyclic voltammetric curves of …


Influence Of Marine Organisms Upon Corrosion Of Steel Piling Systems, Jiunn-Shyong Luo, Cliff Cliff, Rau Rau, Kuei-Ching Chen Aug 2003

Influence Of Marine Organisms Upon Corrosion Of Steel Piling Systems, Jiunn-Shyong Luo, Cliff Cliff, Rau Rau, Kuei-Ching Chen

Journal of Electrochemistry

To study the influence of marine organisms upon corrosion of ASTM A36 steel piling sysems,specimens were immersed in both natural and synthetic seawater.Electrochemical techniques such as linear polarization resistance and electrochemical impedance scan(EIS) were applied to evaluate corrosion of the steel.The results indicated that attachment of marine organisms to form fouling layers on the steel surface reduced general corrosion,but localized corrosion occurred underneath marine organisms.An equivalent circuit model was established to simulate attachment of marine organisms upon carbon carbon steel surfaces.


Electrochemical Impedance Spectroscopy Study On A3 Steel In Anti-Corrosive Pigment Extract Solution, Zhi-Jun Gu, Yong-Gui Liao, Zhi-Gang Zhang, Qi-Long Guo, Fang-Teng Su, Wen-Yun Hu, Yan-Zhen Chen Aug 2001

Electrochemical Impedance Spectroscopy Study On A3 Steel In Anti-Corrosive Pigment Extract Solution, Zhi-Jun Gu, Yong-Gui Liao, Zhi-Gang Zhang, Qi-Long Guo, Fang-Teng Su, Wen-Yun Hu, Yan-Zhen Chen

Journal of Electrochemistry

The corrosion behaviors of A3 steel in different pH, 3.5%NaCl, modified zinc phosphate and aluminum triphosphate extract solutions have been studied by EIS. Results show:(a) The resistance increases with the increase of pH value under the same circumstances, but the capacity is the reverse.(b) Zinc phosphate, because of its low solubility, shows no inhibitive performance for A3 steel in 3.5% NaCl extract solutions. (c) Aluminum triphosphate has good inhibitive performance for A3 steel in 3.5% NaCl extract solutions at a pH of 6, probably because the triphosphate ion can complex with the corrosion_product, such as ferric and ferrous ions, and …


Determination Of Hydrogen Diffusion Coefficient In Metal Hydride Electrode With Electrochemical Impedance Spectroscopy, Xian Xia Yuan, Nai Xin Xu Aug 2001

Determination Of Hydrogen Diffusion Coefficient In Metal Hydride Electrode With Electrochemical Impedance Spectroscopy, Xian Xia Yuan, Nai Xin Xu

Journal of Electrochemistry

Electrochemical impedance spectroscopy was employed to determine the hydrogen diffusion coefficient in MlNi 3.75 Co 0.65 Mn 0.4 Al 0.2 metal hydride electrode with various states of charge(SOC) at room temperature and with 50% SOC at various temperatures. It was found that hydrogen diffusion coefficient in this electrode decreases with the increase in SOC at ambient temperature, and for the electrode with 50%SOC, hydrogen diffusion coefficient increases with the increase of temperature and the activation energy for hydrogen diffusion in it is 35 kJ/mol.