Download or read book SYNTHESIS AND CHARACTERIZATION OF CO AND H sub 2 S TOLERANT ELECTROCATALYSTS FOR PEM FUEL CELL written by Shamsuddin Ilias and published by . This book was released on 2005 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present state-of-art Proton Exchange Membrane Fuel Cell (PEMFC) technology is based on platinum (Pt) as a catalyst for both the fuel (anode) and air (cathode) electrodes. This catalyst is highly active but susceptible to poisoning by CO, which may be present in the H{sub 2}-fuel used or may be introduced during the fuel processing. Presence of trace amount of CO and H{sub 2}S in the H{sub 2}-fuel poisons the anode irreversibly and decreases the performance of the PEMFCs. In an effort to reduce the Pt-loading and improve the PEMFC performance, we propose to synthesize a number of Pt-based binary, ternary, and quaternary electrocatalysts using Ru, Mo, Ir, Ni, and Co as a substitute for Pt. By fine-tuning the metal loadings and compositions of candidate electrocatalysts, we plan to minimize the cost and optimize the catalyst activity and performance in PEMFC. The feasibility of the novel electrocatalysts will be demonstrated in the proposed effort with gas phase CO and H{sub 2}S concentrations typical of those found in reformed fuel gas with coal/natural gas/methanol feedstocks. During this reporting period several tri-metallic electrocatalysts were synthesized using both ultra-sonication and conventional method. These catalysts (Pt/Ru/Mo, Pt/Ru/Ir, Pt/Ru/W, Ptr/Ru/Co, and Pt/Ru/Se on carbon) were tested in MEAs. From Galvonstatic study the catalytic activity was found in the order of: Pt/Ru/Mo/C> Pt/Ru/Ir/C> Pt/Ru/W/C> Ptr/Ru/Co/C> and Pt/Ru/Se. It appears that electrocatalysts prepared by ultra-sonication process are more active compared to the conventional technique. Work is in progress to further study these catalysts for CO-tolerance in PEMFC.
Download or read book Synthesis and Characterization of CO and H2S Tolerant Electrocatalysts for PEM Fuel Cell written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The present state-of-art Proton Exchange Membrane Fuel Cell (PEMFC) technology is based on platinum (Pt) as a catalyst for both the fuel (anode) and air (cathode) electrodes. This catalyst is highly active but susceptible to poisoning by CO, which may be present in the H2-fuel used or may be introduced during the fuel processing. Presence of trace amount of CO in the H2-fuel poisons the anode irreversibly and decreases the performance of the PEMFCs. In an effort to reduce the Pt-loading and improve the PEMFC performance, we have synthesized a number of Pt-based binary, ternary, and quaternary electrocatalysts using Ru, Mo, Ir, Ni, and Co as a substitute for Pt. Co-catalytic activities were found for the elements Mo, Ru, and Ir. Both the ternary (Pt/Ru/Mo/C) and quaternary (Pt/Ru/Mo/Ir/C) metal catalysts in membrane electrode assemblies (MEA) outperformed pure Pt/C catalysts at all levels in presence of CO up to 100 ppm. Preliminary results suggest that by substituting Mo, Ru, and Ir in catalyst formulation, it is possible to reduce Pt-loading and increase CO-tolerance in PEMFC application. Comparison studies showed that the newly developed ternary and quaternary catalysts with lower Pt outperformed pure Pt catalyst in presence of CO-contaminated H2 fuel. High performance at low Pt loading of less than 0.4 mg/cm2 was achieved, thus exceeding the initial targets.
Download or read book PEM Fuel Cell Electrocatalysts and Catalyst Layers written by Jiujun Zhang and published by Springer Science & Business Media. This book was released on 2008-08-26 with total page 1147 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proton exchange membrane (PEM) fuel cells are promising clean energy converting devices with high efficiency and low to zero emissions. Such power sources can be used in transportation, stationary, portable and micro power applications. The key components of these fuel cells are catalysts and catalyst layers. “PEM Fuel Cell Electrocatalysts and Catalyst Layers” provides a comprehensive, in-depth survey of the field, presented by internationally renowned fuel cell scientists. The opening chapters introduce the fundamentals of electrochemical theory and fuel cell catalysis. Later chapters investigate the synthesis, characterization, and activity validation of PEM fuel cell catalysts. Further chapters describe in detail the integration of the electrocatalyst/catalyst layers into the fuel cell, and their performance validation. Researchers and engineers in the fuel cell industry will find this book a valuable resource, as will students of electrochemical engineering and catalyst synthesis.
Download or read book Synthesis and Characterization of Electrocatalyst Libraries for PEM Fuel Cells written by Kousik Ganesan and published by . This book was released on 2005 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: Conversion of energy stored in renewable fuels for sustained and environment friendly operation necessitates new technologies. Polymer electrolyte membrane fuel cells represent an energy conversion technology that has advantages of high operating efficiencies with low hazardous emissions. However the discovery of more active and poison tolerant catalysts for anode and cathode reactions remains a major barrier to commercialization of this technology. The search for improved catalyst formulations is hindered by the massive parameter space available for their construction. Combinatorial methods represent an exploration process well suited to accelerate this discovery through the ability to generate and screen a multitude of compositions in a single experiment. In this work, we describe a combinatorial strategy to generate a wide variety of catalyst compositions (single/binary) and interrogate their activity directly in an electrochemical environment. Catalyst library fabrication tools based upon array deposition methods were used to prepare samples possessing catalyst combinations containing Pt and additional metals such as Ru, Rh, Mo, Ir, Nb, Ta, Pd, Sn, Os and W. High throughput screening of catalytic activity was accomplished by scanning electrochemical microscopy (SECM). Reactivity maps were constructed by directly measuring the kinetics of hydrogen oxidation with a scanning microelectrode probe in the presence and absence of adsorbed carbon monoxide. Results provide quantitative rate constants for hydrogen oxidation and poison tolerance over a broad sampling of catalyst compositions.
Download or read book PEM Fuel Cells written by Gurbinder Kaur and published by Elsevier. This book was released on 2021-11-16 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: PEM Fuel Cells: Fundamentals, Advanced Technologies, and Practical Application provides a comprehensive introduction to the principles of PEM fuel cell, their working condition and application, and the latest breakthroughs and challenges for fuel cell technology. Each chapter follows a systematic and consistent structure with clear illustrations and diagrams for easy understanding. The opening chapters address the basics of PEM technology; stacking and membrane electrode assembly for PEM, degradation mechanisms of electrocatalysts, platinum dissolution and redeposition, carbon-support corrosion, bipolar plates and carbon nanotubes for the PEM, and gas diffusion layers. Thermodynamics, operating conditions, and electrochemistry address fuel cell efficiency and the fundamental workings of the PEM. Instruments and techniques for testing and diagnosis are then presented alongside practical tests. Dedicated chapters explain how to use MATLAB and COMSOL to conduct simulation and modeling of catalysts, gas diffusion layers, assembly, and membrane. Degradation and failure modes are discussed in detail, providing strategies and protocols for mitigation. High-temperature PEMs are also examined, as are the fundamentals of EIS. Critically, the environmental impact and life cycle of the production and storage of hydrogen are addressed, as are the risk and durability issues of PEMFC technology. Dedicated chapters are presented on the economics and commercialization of PEMFCs, including discussion of installation costs, initial capital costs, and the regulatory frameworks; apart from this, there is a separate chapter on their application to the automotive industry. Finally, future challenges and applications are considered. PEM Fuel Cells: Fundamentals, Advanced Technologies, and Practical Application provides an in-depth and comprehensive reference on every aspect of PEM fuel cells fundamentals, ideal for researchers, graduates, and students. Presents the fundamentals of PEM fuel cell technology, electrolytes, membranes, modeling, conductivity, recent trends, and future applications Addresses commercialization, public policy, and the environmental impacts of PEMFC in dedicated chapters Presents state-of-the-art PEMFC research alongside the underlying concepts
Download or read book PEM Fuel Cell Electrocatalysts and Catalyst Layers written by Jiujun Zhang and published by Springer. This book was released on 2010-12-14 with total page 1137 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proton exchange membrane (PEM) fuel cells are promising clean energy converting devices with high efficiency and low to zero emissions. Such power sources can be used in transportation, stationary, portable and micro power applications. The key components of these fuel cells are catalysts and catalyst layers. “PEM Fuel Cell Electrocatalysts and Catalyst Layers” provides a comprehensive, in-depth survey of the field, presented by internationally renowned fuel cell scientists. The opening chapters introduce the fundamentals of electrochemical theory and fuel cell catalysis. Later chapters investigate the synthesis, characterization, and activity validation of PEM fuel cell catalysts. Further chapters describe in detail the integration of the electrocatalyst/catalyst layers into the fuel cell, and their performance validation. Researchers and engineers in the fuel cell industry will find this book a valuable resource, as will students of electrochemical engineering and catalyst synthesis.
Download or read book DEVELOPMENT OF NOVEL ELECTROCATALYSTS FOR PROTON EXCHANGE MEMBRANE FUEL CELLS written by Shamsuddin Ilias and published by . This book was released on 2003 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fuel cells are electrochemical devices that convert the available chemical free energy directly into electrical energy, without going through heat exchange process. Of all different types of fuel cells, the Proton Exchange Membrane Fuel Cell (PEMFC) is one of the most promising power sources for stand-alone utility and electric vehicle applications. Platinum (Pt) Catalyst is used for both fuel and air electrodes in PEMFCs. However, carbon monoxide (CO) contamination of H{sub 2} greatly affects electro catalysts used at the anode of PEMFCs and decreases cell performance. The irreversible poisoning of the anode can occur even in CO concentrations as low as few parts per million (ppm). In this work, we have synthesized several novel elctrocatalysts (Pt/C, Pt/Ru/C, Pt/Mo/C, Pt/Ir and Pt/Ru/Mo) for PEMFCs. These catalysts have been tested for CO tolerance in the H{sub 2}/air fuel cell, using CO concentrations in the H{sub 2} fuel that varies from 10 to 100 ppm. The performance of the electrodes was evaluated by determining the cell potential against current density. The effects of catalyst composition and electrode film preparation method on the performance of PEM fuel cell were also studied. It was found that at 70 C and 3.5 atm pressure at the cathode, Pt-alloy catalyst (10 wt% Pt/Ru/C, 20 wt% Pt/Mo/C) were more CO tolerant than the 20 wt% Pt/C catalyst alone. It was also observed that spraying method was better than the brushing technique for the preparation of electrode film.
Download or read book Synthesis and Characterization of Nano Structured Electrocatalysts for Oxygen Reduction Reaction in Fuel Cells written by Thomas Jefferson Cochell and published by . This book was released on 2013 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proton exchange membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs) are two types of low-temperature fuel cells (LTFCs) that operate at temperatures less than 100 °C and are appealing for portable, transportation, and stationary applications. However, commercialization has been hampered by several problems such as cost, efficiency, and durability. New electrocatalysts must be developed that have higher oxygen reduction reaction (ORR) activity, lower precious metal loadings, and improved durability to become commercially viable. This dissertation investigates the development and use of new electrocatalysts for the ORR. Core-shell (shell@core) Pt@Pd[subscript x]Cu[subscript y]/C electrocatalysts, with a range of initial compositions, were synthesized to result in a Pt-rich shell atop a Pd[subscript x]C[subscript y]-rich core. The interaction between core and shell resulted in a delay in the onset of Pt-OH formation, accounting in a 3.5-fold increase in Pt-mass activity compared to Pt/C. The methanol tolerance of the core-shell Pt@PdCu5/C was found to decrease with increasing Pt-shell coverage due to the negative potential shift in the CO oxidation peak. It was discovered that Cu leached out from the cathode has a detrimental effect on membrane-electrode assembly performance. A spray-assisted impregnation method was developed to reduce particle size and increase dispersion on the support in a consistent manner for a Pd88W12/C electrocatalyst. The spray-assisted method resulted in decreased particle size, improved dispersion and more uniform drying compared to a conventional method. These differences resulted in greater performance during operation of a single DMFC and PEMFC. Additionally, Pd88W12/C prepared by spray-assisted impregnation showed DMFC performance similar to Pt/C with similar particle size in the kinetic region while offering improved methanol tolerance. Pd88W12/C also showed comparable maximum power densities and activities normalized by cost in a PEMFC. Lastly, the activation of aluminum as an effective reducing agent for the wet- chemical synthesis of metallic particles by pitting corrosion was explored along with the control of particle morphology. It was found that atomic hydrogen, an intermediate, was the actual reducing agent, and a wide array of metals could be produced. The particle size and dispersion of Pd/C produced using Al was controlled using PVP and FeCl2 as stabilizers. The intermetallic Cu2Sb was similarly prepared with a 20 nm crystallite size for potential use in lithium-ion battery anodes. Lastly, it was found that the shape of Pd produced with Al as a reducing agent could be controlled to prepare 10 nm cubes enclosed by (100) facets with potentially high activity for the ORR.
Download or read book Recent Development in Energy Conversion Systems written by Sunday Olayinka Oyedepo and published by Frontiers Media SA. This book was released on 2024-03-15 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this industrial and technological age, energy plays a principal role in sustainable development. This is connected to issues regarding availability, production processes, utilization, and environmental impact. Due to the increased rate of population growth, the energy demand in the entire world is getting to the level that it may not be sustained in the nearest future if drastic action is not taken to address the situation, especially from research and development perspectives. "None of the millennium development goals (MDGs) can be completed without considerable improvements in the quality and quantity of energy services in developing countries," according to the United Nations Development Programme (UNDP). Based on this fact, UNDP is making efforts, especially in developing countries to ensure that people have access to sustainable sources of clean, reliable, and affordable energy since every aspect of human development is highly impacted by this vital resource.
Download or read book Catalysis and Electrocatalysis at Nanoparticle Surfaces written by Andrzej Wieckowski and published by CRC Press. This book was released on 2003-02-19 with total page 970 pages. Available in PDF, EPUB and Kindle. Book excerpt: Illustrating developments in electrochemical nanotechnology, heterogeneous catalysis, surface science and theoretical modelling, this reference describes the manipulation, characterization, control, and application of nanoparticles for enhanced catalytic activity and selectivity. It also offers experimental and synthetic strategies in nanoscale surface science. This standard-setting work clariefies several practical methods used to control the size, shape, crystal structure, and composition of nanoparticles; simulate metal-support interactions; predict nanoparticle behavior; enhance catalytic rates in gas phases; and examine catalytic functions on wet and dry surfaces.
Download or read book Energy Materials Coordinating Committe EMaCC Fiscal Year 1998 Annual Technical Report written by and published by DIANE Publishing. This book was released on with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hydrogen Materials Science and Chemistry of Carbon Nanomaterials written by T. Nejat Veziroglu and published by Springer Science & Business Media. This book was released on 2007-05-16 with total page 870 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book considers the various advanced hydrogen materials and technologies of their synthesis. It presents the consideration of the physics, chemistry, thermodynamics and kinetics of processes of energy conversion, which occur at hydrogen production, storage, transportation and with its use. It also discusses the pioneering attempts to transform motor transport, airplanes, domestic technics, illumination and industrial manufacture of hydrogen fuel.
Download or read book Rotating Electrode Methods and Oxygen Reduction Electrocatalysts written by Wei Xing and published by Elsevier. This book was released on 2014-03-26 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rotating Electrode Methods and Oxygen Reduction Electrocatalysts provides the latest information and methodologies of rotating disk electrode and rotating ring-disk electrode (RDE/RRDE) and oxygen reduction reaction (ORR). It is an ideal reference for undergraduate and graduate students, scientists, and engineers who work in the areas of energy, electrochemistry science and technology, fuel cells, and other electrochemical systems. Presents a comprehensive description, from fundamentals to applications, of catalyzed oxygen reduction reaction and its mechanisms Portrays a complete description of the RDE (Rotating Disc Electrode)/RRDE (Rotating Ring-Disc Electrode) techniques and their use in evaluating ORR (Oxygen Reduction Reaction) catalysts Provides working examples along with figures, tables, photos and a comprehensive list of references to help understanding of the principles involved
Download or read book Nano electrocatalyst for Oxygen Reduction Reaction written by Omar Solorza Feria and published by CRC Press. This book was released on 2024-06-21 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: Global warming switches our reliance from fossil fuels to green, sustainable renewable energy sources. Because of its promising nature, high-efficiency nano-electrocatalysts have sparked interest in renewable energy. Hydrogen fuel cell/polymer electrolyte membrane (PEM) vehicles are the most environmentally conscious electromobility vehicles, with a high energy density and quick refuelling technology, prompting the auto industry to launch a variety of PEM fuel cell vehicles around the world. Oxygen reduction reaction (ORR) primary research interests include fuel cells and metal-air batteries. The sluggish kinetic reaction of ORR, which is responsible for the rate-limiting reaction at the PEM fuel cell cathodic system, further decreases energy efficiency. Optimising ORR for market expansion with cost-effective and efficient nano-electrocatalysts, on the other hand, remains a challenge. The book covers fundamental ORR reaction kinetics theories, tools, and techniques. It also explains the nano electrocatalysts for ORR made of noble, non-noble, and nanocarbon materials. Finally, the book explores the applications of PEM fuel cells and metal-air batteries.
Download or read book Development of Co tolerant Anode Electrocatalysts for Fuel Cell Applications written by Ramakrishnan Venkataraman and published by . This book was released on 2000 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electrochemical Oxygen Reduction written by Pei Kang Shen and published by Springer Nature. This book was released on 2021-01-16 with total page 259 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses systematically the theoretical research and the applications of electrochemical oxygen reduction. Oxygen reduction reaction is a common issue in electrochemistry, but is also an important process involved in the field of energy, cryogenic fuel cells, metal–air cells, oxygen sensors and hydrogen peroxide preparation. This book is divided into 6 chapters; it starts with a description of dynamic mechanisms, followed by a detailed introduction on the related experimental methods and related catalyst preparation technology. By providing the basic methods and testing techniques, and by demonstrating their applications, it helps readers gain a better understanding of oxygen reduction reactions, making it a valuable resource for the industrialization of scientific research achievements. Accordingly, the book appeals to a broad readership, particularly graduate students, those working at universities and research organizations, and industrial researchers.
Download or read book Design Synthesis and Characterization of Fuel Cell Electrocatalysts for the Direct Oxidation of Organic Fuels written by Aurora Marie Cabrera Fojas and published by . This book was released on 2008 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt:
