Download or read book The Use of Scanning Electrochemical Microscopy for the Detection and Quantification of Adsorbed Intermediates at Electrodes written by Joaquin Rodriguez Lopez and published by . This book was released on 2010 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scanning electrochemical microscopy (SECM) was used for the study and characterization of catalytic and electrocatalytic processes occurring at electrodes. The Surface Interrogation mode (SI-SECM) was introduced for the detection and quantification of adsorbed intermediates and products of catalyzed chemical and electrochemical reactions at noble metals (Pt, Au). In SI-SECM two micro electrodes (i.e. an SECM tip and a substrate of the desired material) are aligned concentrically at a micrometric distance where SECM feedback effects operate. A contrast mechanism based on feedback effects allows for the detection of reactive adsorbed intermediates at the substrate: the SECM tip generates a reactive homogeneous species that "micro-titrates" the substrate adsorbates to yield an electrochemical signal that contains information about the amount of intermediate and about its kinetics of reaction with the redox mediator. The technique was used for the study of the reactivity of three model small adsorbates: 1) the reactivity of adsorbed oxygen on Au and Pt with a reducing mediator was explored and suggested the detection of "incipient oxides" at these surfaces; kinetic parameters of the reactivity of Pt oxides with mediators were obtained, fit to theory and used to explain observations about the electrocatalytic behavior of Pt under anodizing conditions; 2) the reactivity of oxidizing mediators with adsorbed hydrogen on Pt was studied and showed the cation of N, N, N, N-tetramethyl-p-phenylenediamine (TMPD) to be a successful interrogation agent, the detection of hydrogen generated by the decomposition of formic acid on Pt at open circuit was investigated; 3) electrogenerated bromine was used to catalytically interrogate carbon monoxide at Pt, this reaction was previously unreported. The mentioned applications of SECM were validated through the use of digital simulations of diffusion in the complex SECM geometry through flexible commercial finite element method software.

Download or read book The Study of Localized Corrosion by Scanning Electrochemical Microscopy written by John William Still and published by . This book was released on 1999 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Theory and Experiment in Electrocatalysis written by Perla B. Balbuena and published by Springer. This book was released on 2010-11-02 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Probe Effects During Concentration Determination in Scanning Electrochemical Microscopy written by Alex Mirabal and published by . This book was released on 2022 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: Efficient, sustainable chemical reactions will play a large role in addressing many growing issues, including alternative energy production, greenhouse gas conversion, and pharmaceuticals. Electrochemical reactions are attractive due to their relatively mild reaction conditions and direct use of electricity. The understanding and design of the local liquid-solid interface will guide future progress in electrocatalytic reactions.Over time, nature has evolved many highly efficient reactions through enzymatic reactions. These long-studied catalysts provide complex reaction environments that: 1) enhance interaction with reactants, 2) protect intermediates from side reactions, 3) increase the rates of reactions, and 4) selectively react to a specific product. The overarching lesson to be learned is that the local reaction environment plays a large role in the catalyst's reactivity, selectivity, and efficiency. One way to characterize the local environment is through scanning electrochemical microscopy (SECM), in which a small electrochemical probe is rastered over an interface. A quantitative correlation of the probe response to concentration provides a direct measurement of the local environment.The presence of the SECM probe itself can induce changes in the local environment. Comparing the changed local environment (in situ) to what it would be without the probe present (operando), shows large differences of up to 120% under specific operating conditions. A few physical parameters such as the surface site geometry are shown to have an impact on how significant the probe effects are. Additional parameters such as the tip geometry and tip-surface separation are also to have an impact.A finite element method (FEM) simulation informed by experiments is used to examine the above-mentioned tip effects. It is found that fitting responses to other frequently used electrochemical measurements, such as approach curves and CVs, to parameterize the model appropriately describes experimental SECM results. We first apply this method to study platinum nanoparticles, where a ~50 nm resolution is the highest resolution to our knowledge for AFM-SECM. Through statistical analysis of the surface, an isolated nanoparticle SECM response is correlated with a concentration profile. It is found that the concentration profile has minimal probe effects due to the use of a conical electrode.Applying a similar approach, we also study the probe effects in pH detection during hydrogen evolution and CO2 reduction. Where we match experimental results to parameterize the system. It shown that there is a pH difference of up to ~7 pH units underneath the probe due to hindered diffusion. However, even with these large differences, the probes are still able to reflect the trends seen without the probe present. Moreover, it is shown that the physical parameters have correlated responses, indicating that hindered diffusion is controlled by the insulation radius and tip-surface separation.Finally, the importance of the analyte is discussed with regard to its interaction with the tip. In addition to the concentration impact on the response signal, the compatibility with the tip need be considered. Degradation of the tip and/or the redox couple of choice will detrimentally affect the ability to examine the local interface. We show that, of the redox couples examined, ferrocene-based compounds appear to best satisfy the most crucial factors of stability and mild redox potentials.Overall, this work studies and removes the impact of the probe for local concentration detection using SECM. This work acts as a guide to quantitatively study the local environment of electrocatalyzed reactions. This is realized through a combined experimental-FEM approach in which the simulation is informed by experiments such that it's representative of the experimental environment.

Download or read book Progress in Corrosion Science and Engineering II written by Su-Il Pyun and published by Springer Science & Business Media. This book was released on 2012-02-09 with total page 349 pages. Available in PDF, EPUB and Kindle. Book excerpt: This and volume no. 47 of Modern Aspects of Electrochemistry is composed of eight chapters covering topics having relevance both in corrosion science and materials engineering. In particular, the first seven chapters provide comprehensive coverage of recent advances in corrosion science.

Download or read book The Use of Electrochemical Scanning Tunnelling Microscopy EC STM in Corrosion Analysis written by R Lindstrom and published by Woodhead Publishing. This book was released on 2006-11-30 with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt: The European Federation of Corrosion's Working Party on Surface Science and the Mechanisms of Corrosion and Protection (EFC WP6) has defined, as one of its objectives, the development of a reference material and reference guidelines for the application of electrochemical scanning tunnelling microscopy (EC-STM) in corrosion science. The use of EC-STM to study the relationship between surface structure and surface reactivity in situ on electrodes in contact with an electrolyte is of major importance in corrosion research. This report describes the reference material and procedural guidelines required to use this technique effectively. STM-users are instructed how to obtain high resolution data on a carefully prepared copper single-crystal surface. - Describes the reference material and procedural guidelines required to use this technique effectively - Discusses an area of major importance in corrosion research

Download or read book Scanning Electrochemical Microscopy written by Allen J. Bard and published by CRC Press. This book was released on 2001-04-18 with total page 668 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scanning Electrochemical Microscopy describes the theory and operating principles of scanning electrochemical microscopy (SECM), including instrumentation, tip preparation, imaging techniques and potentiometric probes. The book explores applications relevant to electron transfer reactions, reaction kinetics, chemical events at interfaces, biologica

Download or read book Scanning Electrochemical Microscopy SECM with Amalgam Microelectrodes written by Douglas Alexander Rudolph and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis focuses on in-situ studies at the solid-liquid interface by combining scanning electrochemical microscopy (SECM) with gold and platinum mercury amalgam microelectrodes. It is shown that stripping voltammetry experiments at imaging amalgam microelectrodes provide laterally resolved insight on the electrochemistry of biogeochemically relevant processes. SECM provides information on electroactive surface processes with high spatial resolution, and offers the opportunity to study heterogeneous electron-transfer reactions. Thereby, chemical species of interest, such as metal ions, can be electrochemically detected at mercury amalgam electrodes. Platinum and gold mercury amalgam microelectrodes were developed for the detection of biogeochemically relevant analytes such as manganese and iron during SECM imaging experiments at the mineral/water interface establishing the fundamental basis of SECM imaging with amalgam microelectrodes. SECM experiments were performed for the quantitative determination of Mn2+ during the dissolution of microstructured manganese carbonate (rhodochrosite) precipitates at mildly acidic conditions. SECM images along with spatially resolved quantitative data on the Mn2+ concentration were obtained. This measurement concept was then extended to the investigation of the corrosion behavior of diamond-like carbon (DLC) protected zinc selenide (ZnSe) waveguides applied in mid-infrared attenuated total reflectance spectroscopy at strongly oxidizing conditions. The corrosion behavior of DLC coated and uncoated ZnSe crystals was studied obtaining laterally resolved information on the oxidative degradation of ZnSe at defects of the DLC layer utilizing SECM in combination with square wave anodic stripping voltammetry (SWASV) at gold amalgam microelectrodes. Thereby, insight on the corrosion behavior of ZnSe and concentration profiles of Zn2+ at oxidizing conditions was obtained. These results corroborate the utility of SECM imaging with amalgam microelectrodes for addressing relevant analytical questions. Finally, the developed amalgam microelectrodes were applied for SECM studies of iron-reducing proteins separated from Shewanella microbes in native polyacrylamide gels. After calibration of Pt/Hg microelectrodes in bulk solution for the targeted analytes (iron and sulfur species), SECM approach curves recorded above the native gel enabled positioning of the amalgam electrode in close proximity above protein bands with suspected iron-reducing activity. This technique enabled the (semi)quantitative determination of the anaerobic respiratory activity associated with microbial proteins/protein complexes responsible for the reductive dissolution of manganese and iron oxides above microbial protein bands separated in a native gel matrix.

Download or read book Investigation of Electron Transfer Processes and Surface Modifications with Scanning Electrochemical Microscopy SECM written by Marisa Sheffer and published by . This book was released on 2008 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Electrochemical and Optical Techniques for the Study and Monitoring of Metallic Corrosion written by M.G.S Ferreira and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 714 pages. Available in PDF, EPUB and Kindle. Book excerpt: In spite of considerable efforts over the years to understand and combat materials degradation via corrosion processes, many challenges still remain both in the theoretical understanding of the phenomena and in seeking pratical solutions to the perennial problem. Progress has been slow due to the complexity of the processes and the systems involved. Fortunately, in recent years there has been a renaissance in the development of new electrochemical and optical techniques, as well as advances in instrumentation, which have greatly aided our quest to gain insight into the complex mechanisms involved in metallic corrosion and passivation. Numerous scientific meetings, symposia, and workshops have been held allover the world which attest to the frenzy of activities in corrosion science and technology. However, most of these conferences have dealt mainly with recent research results. There appeared to be a need to assess and disseminate our present state of knowledge in the field as regards measurement techniques, theory, and instrumentation. The present NATO Advanced Study Institute was therefore held in Viana do Castelo, Portugal from July 9 to 21, 1989. The Institute consisted of a series of tutorial lectures, poster sessions, and round-table discussions interspersed evenly over the two-week period. It was attended by 75 participants from several countries representing industry, government and university laboratories.

Download or read book Instationary Processes and Dynamic Experimental Methods in Catalysis Electrochemistry and Corrosion written by Gerd Sandstede and published by Wiley-VCH. This book was released on 1989 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Electrochemical Impedance Spectroscopy written by Mark E. Orazem and published by John Wiley & Sons. This book was released on 2011-10-13 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using electrochemical impedance spectroscopy in a broad range of applications This book provides the background and training suitable for application of impedance spectroscopy to varied applications, such as corrosion, biomedical devices, semiconductors and solid-state devices, sensors, batteries, fuel cells, electrochemical capacitors, dielectric measurements, coatings, electrochromic materials, analytical chemistry, and imaging. The emphasis is on generally applicable fundamentals rather than on detailed treatment of applications. With numerous illustrative examples showing how these principles are applied to common impedance problems, Electrochemical Impedance Spectroscopy is ideal either for course study or for independent self-study, covering: Essential background, including complex variables, differential equations, statistics, electrical circuits, electrochemistry, and instrumentation Experimental techniques, including methods used to measure impedance and other transfer functions Process models, demonstrating how deterministic models of impedance response can be developed from physical and kinetic descriptions Interpretation strategies, describing methods of interpretating of impedance data, ranging from graphical methods to complex nonlinear regression Error structure, providing a conceptual understanding of stochastic, bias, and fitting errors in frequency-domain measurements An overview that provides a philosophy for electrochemical impedance spectroscopy that integrates experimental observation, model development, and error analysis This is an excellent textbook for graduate students in electrochemistry, materials science, and chemical engineering. It's also a great self-study guide and reference for scientists and engineers who work with electrochemistry, corrosion, and electrochemical technology, including those in the biomedical field, and for users and vendors of impedance-measuring instrumentation.

Download or read book Catalysis and Electrocatalysis at Nanoparticle Surfaces written by Andrzej Wieckowski and published by CRC Press. This book was released on 2019-08-30 with total page 970 pages. Available in PDF, EPUB and Kindle. Book excerpt: Catalysis and Electrocatalysis at Nanoparticle Surfaces illustrates the latest developments in electrochemical nanotechnology, heterogeneous catalysis, surface science, and theoretical modeling. It describes the manipulation, characterization, control, and application of nanoparticles for enhanced catalytic activity and selectivity and presents a range of experimental and synthetic strategies for work in nanoscale surface science. Thisis a comprehensive source for physical, surface, and colloid chemists; materials scientists; interfacial chemists and electrochemists; electrochemical engineers; theoretical physicists; chemical engineers; and upper-level undergraduate and graduate students in these disciplines.

Download or read book Nanoelectrochemistry written by Michael V. Mirkin and published by CRC Press. This book was released on 2015-03-27 with total page 852 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanoscale electrochemistry has revolutionized electrochemical research and technologies and has impacted other fields, including nanotechnology and nanoscience, biology, and materials chemistry. This book examines well-established concepts and principles and provides an updated overview of the field and its applications. The first two chapters contain theoretical background, specifically, theories of electron transfer, transport, and double-layer processes at nanoscale electrochemical interfaces. The next chapters examine the electrochemical studies of nanomaterials and nanosystems, as well as the applications of nanoelectrochemical techniques. Each chapter can be read independently, providing readers with a compact, up-to-date review of th

Download or read book Lectures on Electrochemical Corrosion written by Marcel Pourbaix and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Workers in the field of corrosion and their students are most fortunate that a happy set of circumstances brought Dr. Marcel Pourbaix into their field in 1949. First, he was invited, while in the USA, to demonstrate at a two week visit to the National Bureau of Standards the usefulness of his electro chemical concepts to the study of corrosion. Secondly, also around the same time, Prof. H. H. Uhlig made a speech before the United Nations which pointed out the tremendous economic consequences of corrosion. Because of these circumstances, Dr. Pourbaix has reminisced, he chose to devote most of his efforts to corrosion rather than to electrolysis, batteries, geology, or any of the other fields where, one might add, they were equally valuable. This decision resulted in his establishing CEBELCOR (Centre BeIge d'Etude de la Corrosion) and in his development of a course at the Free University of Brussels entitled "Lectures on Electrochemical Corrosion." This book is the collection of these lectures translated into English.

Download or read book Tools and Trends in Bioanalytical Chemistry written by Lauro Tatsuo Kubota and published by Springer Nature. This book was released on 2021-11-25 with total page 559 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook covers the main tools and techniques used in bioanalysis, provides an overview of their principles, and offers several examples of their application and future trends in diagnosis. Chapters from expert contributors explore the role of bioanalysis in different areas such as biochemistry, physiology, forensics, and clinical diagnosis, including topics from sampling/sample preparation, chemometrics in bioanalysis to the latest techniques used in the field. Particular attention is given to the recent advances in the application of mass spectrometry, NMR, electrochemical methods and separation techniques in bioanalysis. Readers will also find more about the application of microchip-based devices and analytical microarrays. This textbook will appeal to graduate/advanced undergraduate students in Chemistry, Biology, Biochemistry, Pharmacy, and Chemical Engineering. It is also a useful resource for researchers and professionals working in the fields of biomedicine and veterinary sciences, with clear explanations and examples of how the different bioanalytical devices are applied for clinical diagnosis.

Download or read book Progress in Corrosion Science and Engineering I written by Su-Il Pyun and published by Springer. This book was released on 2014-11-21 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present volume of Modern Aspects of Electrochemistry is composed of four chapters covering topics having relevance both in corrosion science and materials engineering. All of the chapters provide comprehensive coverage of recent advances in corrosion science. The first chapter, by Maurice and Marcus, provides a comprehensive review on the structural aspects and anti-corrosion properties of passive films on metals and alloys. These authors look at recent experimental data collected by in-situ microscopic techniques coupled with electrochemical methods. A detailed description is given of the nucleation and growth of 2-dimensional passive films at earlier stages, their effect on the corrosion properties of metal surfaces, and the nanostructures of- dimensional passive films. On the basis of the experimental data reviewed, the authors present a model for passivity breakdown and pit initiation, which takes into account the preferential role of grain boundaries. In Chapter 2, Takahashi and his co-workers give a specialized account on the electrochemical and structural properties of anodic oxide films formed on aluminum. In addition to the electrochemical corrosion-related problems of anodic oxide films, the chapter reviews state-of-the-art research of nano-/mic- fabrications based on anodizing treatments combined with chemical/mechanical processes such as laser irradiation, atomic force micro-probe processing and thin film deposition techniques.