Download or read book Electrochemical Synthesis and Characterisation of Multimetallic Nanostructured Electrocatalysts written by Tumaini S. P. Mkwizu and published by . This book was released on 2015 with total page 662 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis concerns investigations on novel multistage electrochemical deposition of nanostructured systems composed of noble metals platinum, ruthenium, and gold. Various electrochemical synthetic pathways were systematically explored producing multilayered nanoscale electrode systems composed of Pt, Ru, or Au on glassy carbon or crystalline gold used as substrates. Electrochemical pathways involved sequential surface-limited redox-replacement (SLRR) reactions of underpotentially-deposited or overpotentially-deposited copper, potentiostatic dealloying, direct spontaneous deposition of noble metals (without intermediary steps involving redox-replacement templating reactions) as well as sequential codeposition of noble metals (with or without SLRR templating reactions). Fundamental studies were conducted using thermodynamic and kinetic models, in situ electrochemical techniques and ex situ microscopic, spectroscopic, or spectrophotometric techniques employed for probing factors controlling electrode dynamics, electrocatalysis, morphology, bulk and surface compositional properties of the noble metal-based electrode systems. Unique multilayered multimetallic nanoclusters synthesized (with binary active sites of Pt with Ru or Au) exhibited superior electrocatalytic activity towards methanol or formic acid oxidation reactions when benchmarked to equivalent monometallic multilayered Pt. Hydrodynamic electrokinetic studies of the oxygen reduction reaction (ORR) on the multilayered monometallic Pt and bimetallic Rucontaining nanoclusters revealed that the monometallic nanoclusters exhibited direct four-electron ORR whereas electrocatalysis on the bimetallic ones could be tuned to proceed via a two-electron reaction pathway. Electrocatalytic bifunctional reaction mechanisms were especially enhanced by the nanostructured systems investigated. Characterisation of multilayered nanoclusters surface and near-surface metal contents revealed interactions between metal centers, car.

Download or read book Synthesis and Characterization of Nanostructured Electrocatalysts by Hydrophobic Nanoreactor Templating written by Tobias Unmüssig and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synthesis and Characterization of Nanostructured Palladium based Alloy Electrocatalysts written by Arindam Sarkar and published by . This book was released on 2009 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: Low temperature fuel cells like proton exchange membrane fuel cells (PEMFC) are expected to play a crucial role in the future hydrogen economy, especially for transportation applications. These electrochemical devices offer significantly higher efficiency compared to conventional heat engines. However, use of exotic and expensive platinum as the electrocatalyst poses serious problems for commercial viability. In this regard, there is an urgent need to develop low-platinum or non-platinum electrocatalysts with electrocatalytic activity for the oxygen reduction reaction (ORR) superior or comparable to that of platinum. This dissertation first investigates non-platinum, palladium-based alloy electrocatalysts for ORR. Particularly, Pd-M (M = Mo and W) alloys are synthesized by a novel thermal decomposition of organo-metallic precursors. The carbon-supported Pd-M (M = Mo, W) electrocatalyts are then heat treated up to 900 °C in H2 atmosphere and investigated for their phase behavior. Cyclic voltammetry (CV) and rotating disk electrode (RDE) measurements reveal that the alloying of Pd with Mo or W significantly enhances the catalytic activity for ORR as well as the stability (durability) of the electrocatalysts. Additionally, both the alloy systems exhibit high tolerance to methanol, which is particularly advantageous for direct methanol fuel cells (DMFC). The dissertation then focuses on one-pot synthesis of carbon-supported multi-metallic Pt-Pd-Co nanoalloys by a rapid microwave-assisted solvothermal (MW-ST) method. The multi-metallic alloy compositions synthesized by the MW-ST method show much higher catalytic activity for ORR compared to their counterparts synthesized by the conventional borohydride reduction method. Additionally, a series of Pt encapsulated Pd-Co nanoparticle electrocatalysts are synthesized by the MW-ST method and characterized to understand their phase behavior, surface composition, and electrocatalytic activity for ORR. Finally, the dissertation focuses on carbon-supported binary Pt@Cu and ternary PtxPd1-x@Cu "core-shell" nanoparticles synthesized by a novel galvanic displacement of Cu by Pt4+ and Pd2+ at ambient conditions. Structural characterizations suggest that the Pt@Cu nanoparticles have a Pt-Cu alloy layer sandwiched between a copper core and a Pt shell. The electrochemical data clearly point to an enhancement in the activity for ORR for the Pt@Cu "core-shell" nanoparticle electrocatalysts compared to the commercial Pt electrocatalyst, both on per unit mass of Pt and per unit active surface area basis. The increase in activity for ORR is ascribed to electronic modification of the outer Pt shell by the Pt-Cu alloy core. However, incorporation of Pd to obtain PtxPd1-x@Cu deteriorates the activity for ORR.

Download or read book Synthesis and Characterization of Nanostructured Carbon Supported Pt based Electrocatalysts written by Geng, Xi and published by . This book was released on 2012 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Fuel cell, as an alternative green power source for automobiles and portable electronics, has attracted worldwide attention due to its desirable properties such as high energy density and low greenhouse gas emission. Despite great progress in the past decades, several challenges still remain as obstacles for the large-scale commercialization. Among them, the high cost of Pt-based electrode material is considered as a major barrier, while the life span or stability of electrode catalysts is another concern since the electrocatalysts can be easily poisoned during the fuel cell operation. In order to overcome these issues, nanostructured carbon materials, especially carbon nanotubes (CNTs), are studied as catalyst support. In addition, recent research also suggests that the coupling of a second metal element with Pt can effectively protect the electrocatalysts from being poisoned and thus improve their long-term durability. The objective of the present work was to demonstrate an efficient synthetic method for the preparation of CNTs supported binary PtM (M=Ru, Sn) electrocatalysts. In this project, a polymer wrapping technique along with an in-situ polyol reduction strategy was adopted to decorate well-dispersed binary PtM nanoparticles on the surface of modified-CNTs. The unique nanostructures as well as the excellent catalytic activities of the as-prepared nanohybirds were investigated through a diversity of physiochemical and electrochemical characterization techniques. This fabrication method provided a simple and convenient route to assemble Pt-based catalyst on carbon substrates, which is useful for the further development of high-performance fuel cell catalysts.

Download or read book Nanoelectrocatalysts for Energy and Water Treatment written by Kumar Raju (Writer on nanostructured materials) and published by Springer Nature. This book was released on 2024 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanomaterials have recently garnered significant attention and practical importance for heterogeneous electrocatalysis. This book presents recent developments in the design, synthesis, and characterisation of nanostructured electrocatalytic materials, with a focus on applications to energy and wastewater treatment. Electrocatalytic nanomaterials can enhance process efficiency and sustainability, thus providing innovative solutions for a wide array of areas such as sustainable energy production, conversion, and wastewater treatment. Readers will gain insights into the latest breakthroughs in electrocatalysis and the activity of nanomaterials in energy conversion applications, e.g., fuel cells, hydrogen production, water splitting, and electro/photocatalytic water splitting, as well as for wastewater treatment. The book explores the development of advanced electrocatalysts, particularly hybrid materials.

Download or read book Metal Oxide Based Nanostructured Electrocatalysts for Fuel Cells Electrolyzers and Metal Air Batteries written by Teko Napporn and published by Elsevier. This book was released on 2021-01-30 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal Oxide-Based Nanostructured Electrocatalysts for Fuel Cells, Electrolyzers, and Metal-Air Batteries is a comprehensive book summarizing the recent overview of these new materials developed to date. The book is motivated by research that focuses on the reduction of noble metal content in catalysts to reduce the cost associated to the entire system. Metal oxides gained significant interest in heterogeneous catalysis for basic research and industrial deployment. Metal Oxide-Based Nanostructured Electrocatalysts for Fuel Cells, Electrolyzers, and Metal-Air Batteries puts these opportunities and challenges into a broad context, discusses the recent researches and technological advances, and finally provides several pathways and guidelines that could inspire the development of ground-breaking electrochemical devices for energy production or storage. Its primary focus is how materials development is an important approach to produce electricity for key applications such as automotive and industrial. The book is appropriate for those working in academia and R&D in the disciplines of materials science, chemistry, electrochemistry, and engineering. Includes key aspects of materials design to improve the performance of electrode materials for energy conversion and storage device applications Reviews emerging metal oxide materials for hydrogen production, hydrogen oxidation, oxygen reduction and oxygen evolution Discusses metal oxide electrocatalysts for water-splitting, metal-air batteries, electrolyzer, and fuel cell applications

Download or read book Fabrication of Metal Organic Framework Derived Nanomaterials and Their Electrochemical Applications written by Wei Xia and published by Springer. This book was released on 2018-04-03 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis systematically introduces readers to a new metal-organic framework approach to fabricating nanostructured materials for electrochemical applications. Based on the metal-organic framework (MOF) approach, it also demonstrates the latest ideas on how to create optimal MOF and MOF-derived nanomaterials for electrochemical reactions under controlled conditions. The thesis offers a valuable resource for researchers who want to understand electrochemical reactions at nanoscale and optimize materials from rational design to achieve enhanced electrochemical performance. It also serves as a useful reference guide to fundamental research on advanced electrochemical energy storage materials and the synthesis of nanostructured materials.

Download or read book Synthesis Characterization and Electrochemical Applications of Nanostructured Non precious Metal Catalysts written by Zhichao Wang and published by . This book was released on 2012 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fundamentals of Electrocatalyst Materials and Interfacial Characterization written by Nicolas Alonso-Vante and published by John Wiley & Sons. This book was released on 2019-02-26 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses some essential topics in the science of energy converting devices emphasizing recent aspects of nano-derived materials in the application for the protection of the environment, storage, and energy conversion. The aim, therefore, is to provide the basic background knowledge. The electron transfer process and structure of the electric double layer and the interaction of species with surfaces and the interaction, reinforced by DFT theory for the current and incoming generation of fuel cell scientists to study the interaction of the catalytic centers with their supports. The chief focus of the chapters is on materials based on precious and non-precious centers for the hydrogen electrode, the oxygen electrode, energy storage, and in remediation applications, where the common issue is the rate-determining step in multi-electron charge transfer processes in electrocatalysis. These approaches are used in a large extent in science and technology, so that each chapter demonstrates the connection of electrochemistry, in addition to chemistry, with different areas, namely, surface science, biochemistry, chemical engineering, and chemical physics.

Download or read book Nanotechnology in Electrocatalysis for Energy written by Alessandro Lavacchi and published by Springer Science & Business Media. This book was released on 2014-01-28 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on nanotechnology in electrocatalysis for energy applications. In particular the book covers nanostructured electrocatalysts for low temperature fuel cells, low temperature electrolyzers and electrochemical valorization. The function of this book is to provide an introduction to basic principles of electrocatalysis, together with a review of the main classes of materials and electrode architectures. This book will illustrate the basic ideas behind material design and provide an introductory sketch of current research focuses. The easy-to-follow three part book focuses on major formulas, concepts and philosophies. This book is ideal for professionals and researchers interested in the field of electrochemistry, renewable energy and electrocatalysis.

Download or read book Electrochemical Synthesis of Nanoengineered Materials and Their Applications written by Nosang Vincent Myung and published by Frontiers Media SA. This book was released on 2019-12-27 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modern Electrochemical Methods in Nano Surface and Corrosion Science written by Mahmood Aliofkhazraei and published by BoD – Books on Demand. This book was released on 2014-06-11 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: The basics and principles of new electrochemical methods and also their usage for fabrication and analysis of different nanostructures were discussed in this book. These methods consist of electrochemical methods in nanoscale (e.g. electrochemical atomic force microscopy and electrochemical scanning tunneling microscopy) and also electrochemical methods for fabrication of nanomaterials.

Download or read book Synthesis and Characterization of Nanostructured Materials for Electrochemical and Catalytic Applications written by Fanglin Chen and published by . This book was released on 2001 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nanostructured Materials for Electrochemical Energy Production and Storage written by Edson Roberto Leite and published by Springer Science & Business Media. This book was released on 2010-03-20 with total page 241 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here is an authoritative reference from world-renowned research groups for those working in materials science and electrochemistry. The authors describe properties of nanostructured materials that can improve performance in alternative energy devices.

Download or read book Synthesis and Characterization of Nanostructured Electrocatalysts for Proton Exchange Membrane and Direct Methanol Fuel Cells written by Liufeng Xiong and published by . This book was released on 2004 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proton exchange membrane fuel cells (PEMFC) and direct methanol fuel cells (DMFC) are attractive power sources as they offer high conversion efficiencies with low or no pollution. However, the most commonly used platinum electrocatalyst is expensive and the world supply of Pt is limited. In addition, the slow oxygen reduction and methanol oxidation kinetics as well as the poisoning of the Pt catalyst at the cathode resulting from methanol permeation from the anode through the Nafion membrane to the cathode lead to significant performance loss. Also, the electrocatalyst utilization in the electrodes also needs to be improved to reduce the overall cost of the electrocatalysts and improve the fuel cell performance. This dissertation explores nanostructured Pt alloys with lower cost and higher catalytic activity than Pt for oxygen reduction in PEMFC to understand the effect of synthesis and structure on the catalytic activity, methanol tolerant Pt/TiOx nanocomposites for oxygen reduction in DMFC, nanostructured Pt-Ru alloys for methanol oxidation in DMFC, and improvement in the utilization of Pt by optimizing the membrane-electrode assembly (MEA) fabrication. From a systematic investigation of a series of Pt-M alloys (M = Fe, Co, Ni, and Cu), the catalytic activity of Pt-M alloys is correlated with the extent of atomic ordering. More ordered Pt alloys exhibit higher catalytic activity than disordered Pt alloys. The higher activity of the ordered Pt alloys is found to relate to various factors including the Pt-Pt distance, Pt: 5d orbital vacancy, {100} planar density and surface atomic configuration. The catalytic activity of the Pt alloys is also influenced by the synthesis method. Low temperature solution methods usually result in smaller particle size and higher surface area, while high temperature routes result in larger particle size and lower surface area but with a greater extent of alloying. Pt/TiOx/C nanocomposites exhibit higher performance than Pt for oxygen reduction in DMFC. The nanocomposites show higher electrchochemical surface area, lower charge transfer resistance, and higher methanol tolerance than Pt. Pt-Ru alloy synthesized by a reverse microemulsion method exhibits higher catalytic surface area than the commercial Pt-Ru. The higher catalytic activity is attributed to a better control of the particle size, crystallinity, and microstructure. Membrane-electrode assemblies (MEAs) fabricated by a modified thin film method exhibit much higher electrocatalyst utilization efficiency and performance than the conventional MEAs in PEMFC. Power densities of 715 and 610 mW/cm2 are obtained at a Pt loading of, respectively, 0.1 and 0.05 mg/cm2 and 90 oC. The higher electrocatalyst utilization is attributed to the thin catalyst layer and a better continuity of the membrane/catalysts layer interface compared to that in the conventional MEAs.

Download or read book Electrochemical water splitting based on metal oxide composite nanostructures written by Aneela Tahira and published by Linköping University Electronic Press. This book was released on 2020-05-14 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: The occurrence of available energy reservoirs is decreasing steeply, therefore we are looking for an alternative and sustainable renewable energy resources. Among them, hydrogen is considered as green fuel with a high density of energy. In nature, hydrogen is not found in a free state and it is most likely present in the compound form for example H2O. Water covers almost 75% of the earth planet. To produce hydrogen from water, it requires an efficient catalyst. For this purpose, noble materials such as Pt, Ir, and Ru are efficient materials for water splitting. These precious catalysts are rare in nature, very costly, and are restricted from largescale applications. Therefore, search for a new earth-abundant and nonprecious materials is a hot spot area in the research today. Among the materials, nanomaterials are excellent candidates because of their potential properties for extended applications, particularly in energy systems. The fabrication of nanostructured materials with high specific surface area, fast charge transport, rich catalytic sites, and huge ion transport is the key challenge for turning nonprecious materials into precious catalytic materials. In this thesis, we have investigated nonprecious nanostructured materials and they are found to be efficient for electrochemical water splitting. These nanostructured materials include MoS2-TiO2, MoS2, TiO2, MoSx@NiO, NiO, nickeliron layered double hydroxide (NiFeLDH)/Co3O4, NiFeLDH, Co3O4, Cu-doped MoS2, Co3O4- CuO, CuO, etc. The composition, morphology, crystalline structure, and phase purities are investigated by a wide range of analytical instruments such as XPS, SEM, HRTEM, and XRD. The production of hydrogen/oxygen from water is obtained either in the acidic or alkaline media. Based on the functional characterization we believe that these newly produced nanostructured materials can be capitalized for the development of water splitting, batteries, and other energy-related devices.

Download or read book Nanomaterials for Electrocatalysis written by Thandavarayan Maiyalagan and published by Elsevier. This book was released on 2022-01-28 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanomaterials for Electrocatalysis provides an overview of the different types of nanomaterials, design principles and synthesis protocols used for electrocatalytic reactions. The book is divided into four parts that thoroughly describe basic principles and fundamental of electrocatalysis, different types of nanomaterials used, and their electrocatalytic applications, limitations and future perspectives. As electrochemical systems containing nanomaterials, with relevance to experimental situation, yield better results, this book highlights new information and findings. Provides an overview of nanomaterials applications for electrocatalytic processes, such as oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER) and CO2 reduction reaction (CO2RR) Provides information on the design and development of various nanomaterials appropriate for electrocatalytic applications Assesses the challenges of manufacturing nanomaterials at an industrial scale for electronic applications