Download or read book Correlating Electronic and Catalytic Properties of Bimetallic Surfaces for Model Hydrogenation Reactions written by Amit Goda and published by ProQuest. This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The formation of bimetallic surfaces leads to a change in the electronic properties of the parent metal surface, which results in changes in chemical reactivity. The activity and selectivity of reactions on transition metal surfaces can be increased by creation of such bimetallic combinations. In this dissertation, the correlation of electronic properties of bimetallic surfaces with the reaction pathways of C 2 hydrocarbons, catalytic properties of higher alkenes and selective reduction of acetic acid to acetaldehyde is illustrated. For the study on C 2 hydrocarbons, Density Functional Theory (DFT) was used to study the binding of hydrogen, ethylene, acetylene, ethyl and vinyl on monometallic and bimetallic transition metal surfaces. The binding energies (B.E.) of these species were found to correlate with the d-band centers of the surfaces. DFT-calculated B.E. and BOC-calculated activation barrier values were used to calculate the selectivity for acetylene hydrogenation vs. ethylene hydrogenation. The results showed that for monometallic fcc(111) surfaces, the selectivity for acetylene hydrogenation followed the trend Ni> Pt> Pd. In addition, the general trend in the binding energy of other alkenes, including butene, pentane, hexene, and cyclohexene also followed similar binding energy trend as compared to ethylene. Adsorption studies were also carried out for benzene in two favorable configurations. Along with the adsorption trends, DFT based studies were carried out to study the effect of hydrocarbon chain length and cyclization on the adsorption on Pt-based bimetallic surfaces. In the case of selective reduction of acetic acid, DFT calculations were used to study the modes and energies of adsorption of the involved intermediates along with the overall reaction energies for the elementary steps. DFT calculations on acetic acid, acetaldehyde and ethanol showed that the binding energy (B.E.) of the molecules decreases as the surface d-band center shifts away from the Fermi level. It was observed that ethanol binds more strongly than acetaldehyde on Pt(111) as well as the subsurface Ni on Pt (Pt-Ni-Pt) surface, but the trend reverses when Ni is on top of Pt (Ni-Pt-Pt). This change in B.E. affects the overall heat of reaction for ethoxy going to ethanol, making it highly exothermic on Pt(111) and Pt-Ni-Pt surfaces, while it is endothermic on the Ni-Pt- Pt surface. These changes in the thermodynamics of reactions should affect the rate determining steps toward selective acetaldehyde formation, which was determined by calculating the activation barriers for the elementary steps.
Download or read book Bimetallic Catalysts written by John H. Sinfelt and published by Wiley-Interscience. This book was released on 1983-09-29 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents an account of the research on bimetallic catalysts. Focuses attention on the possibility of influencing the selectivity of chemical transformations on metal surfaces and preparing metal alloys in a highly dispersed state. Covers the validation and elucidation of the bimetallic cluster concept. Includes figures and tables.
Download or read book Controlling Hydrogenation Activity and Selectivity of Bimetallic Surfaces and Catalysts written by Luis E. Murillo and published by ProQuest. This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nanotechnology in Catalysis Volumes 1 and 2 written by Bing Zhou and published by Springer Science & Business Media. This book was released on 2003-12-31 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is mainly based on the first and second symposia on Nanotechnology in Catalysis held in 2001 and 2002, but it also includes several contributions not presented in the symposia to round out the scope of the subject. The contents are the most up to date developments made by researchers all over the world in the catalysis field in this fascinating nanotechnology era. It reflects some of the frontier areas of nanoscience and nanotechnology in fabricating and characterizing catalysts and carrying out studies to prove their superior selectivity and activity. The field of application of nanotechnology for the development of catalysts for green chemistry is likely to grow rapidly during the next decade. This book hopes to contribute to the evolution of nanotechnology in that direction.
Download or read book Design of Heterogeneous Catalysts written by Umit S. Ozkan and published by John Wiley & Sons. This book was released on 2009-02-11 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: This long-awaited reference source is the first book to focus on this important and hot topic. As such, it provides examples from a wide array of fields where catalyst design has been based on new insights and understanding, presenting such modern and important topics as self-assembly, nature-inspired catalysis, nano-scale architecture of surfaces and theoretical methods. With its inclusion of all the useful and powerful tools for the rational design of catalysts, this is a true "must have" book for every researcher in the field.
Download or read book Bimetallic Nanostructures written by Ya-Wen Zhang and published by John Wiley & Sons. This book was released on 2018-05-14 with total page 525 pages. Available in PDF, EPUB and Kindle. Book excerpt: Systematically summarizes the current status and recent advances in bimetallic structures, their shape-controlled synthesis, properties, and applications Intensive researches are currently being carried out on bimetallic nanostructures, focusing on a number of fundamental, physical, and chemical questions regarding their synthesis and properties. This book presents a systematic and comprehensive summary of the current status and recent advances in this field, supporting readers in the synthesis of model bimetallic nanoparticles, and the exploration and interpretation of their properties. Bimetallic Nanostructures: Shape-Controlled Synthesis for Catalysis, Plasmonics and Sensing Applications is divided into three parts. Part 1 introduces basic chemical and physical knowledge of bimetallic structures, including fundamentals, computational models, and in situ characterization techniques. Part 2 summarizes recent developments in synthetic methods, characterization, and properties of bimetallic structures from the perspective of morphology effect, including zero-dimensional nanomaterials, one-dimensional nanomaterials, and two-dimensional nanomaterials. Part 3 discusses applications in electrocatalysis, heterogeneous catalysis, plasmonics and sensing. Comprehensive reference for an important multidisciplinary research field Thoroughly summarizes the present state and latest developments in bimetallic structures Helps researchers find optimal synthetic methods and explore new phenomena in surface science and synthetic chemistry of bimetallic nanostructures Bimetallic Nanostructures: Shape-Controlled Synthesis for Catalysis, Plasmonics and Sensing Applications is an excellent source or reference for researchers and advanced students. Academic researchers in nanoscience, nanocatalysis, and surface plasmonics, and those working in industry in areas involving nanotechnology, catalysis and optoelectronics, will find this book of interest.
Download or read book Catalytic and Process Study of the Selective Hydrogenation of Acetylene and 1 3 Butadiene written by Ruijun Hou and published by Springer. This book was released on 2017-01-05 with total page 151 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis offers novel methods for catalyst and process design for the selective hydrogenation of acetylene and 1,3-butadiene. The author predicts the properties of supported Pd–Ni bimetallic catalysts using density functional theory (DFT) calculations and temperature-programmed desorption (TPD). The excellent correlation between model surfaces and supported catalysts demonstrates the feasibility of designing effective bimetallic catalysts for selective hydrogenation reactions. The author also proposes a method for designing non-precious metal catalysts to replace precious metals. She modifies the process of selective hydrogenation of acetylene by coupling the selective adsorption to the selective hydrogenation in the liquid phase, as a result of which the ethylene selectivity is greatly improved and heat transfer is greatly enhanced. Lastly, by analyzing the mechanism of liquid-phase hydrogenation, the author proposes a multi-stage slurry bed reactor for industrial applications.“/p>
Download or read book Sustainable Ammonia Production written by Inamuddin and published by Springer Nature. This book was released on 2020-01-09 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents sustainable synthetic pathways and modern applications of ammonia. It focuses on the production of ammonia using various catalytic systems and its use in fuel cells, membrane, agriculture, and renewable energy sectors. The book highlights the history, investigation, and development of sustainable pathways for ammonia production, current challenges, and state-of-the-art reviews. While discussing industrial applications, it fills the gap between laboratory research and viable applications in large-scale production.
Download or read book Bimetallic Nanostructures written by Ya-Wen Zhang and published by John Wiley & Sons. This book was released on 2018-05-16 with total page 738 pages. Available in PDF, EPUB and Kindle. Book excerpt: Systematically summarizes the current status and recent advances in bimetallic structures, their shape-controlled synthesis, properties, and applications Intensive researches are currently being carried out on bimetallic nanostructures, focusing on a number of fundamental, physical, and chemical questions regarding their synthesis and properties. This book presents a systematic and comprehensive summary of the current status and recent advances in this field, supporting readers in the synthesis of model bimetallic nanoparticles, and the exploration and interpretation of their properties. Bimetallic Nanostructures: Shape-Controlled Synthesis for Catalysis, Plasmonics and Sensing Applications is divided into three parts. Part 1 introduces basic chemical and physical knowledge of bimetallic structures, including fundamentals, computational models, and in situ characterization techniques. Part 2 summarizes recent developments in synthetic methods, characterization, and properties of bimetallic structures from the perspective of morphology effect, including zero-dimensional nanomaterials, one-dimensional nanomaterials, and two-dimensional nanomaterials. Part 3 discusses applications in electrocatalysis, heterogeneous catalysis, plasmonics and sensing. Comprehensive reference for an important multidisciplinary research field Thoroughly summarizes the present state and latest developments in bimetallic structures Helps researchers find optimal synthetic methods and explore new phenomena in surface science and synthetic chemistry of bimetallic nanostructures Bimetallic Nanostructures: Shape-Controlled Synthesis for Catalysis, Plasmonics and Sensing Applications is an excellent source or reference for researchers and advanced students. Academic researchers in nanoscience, nanocatalysis, and surface plasmonics, and those working in industry in areas involving nanotechnology, catalysis and optoelectronics, will find this book of interest.
Download or read book Investigating the Surface Chemistry of Hydrogenation Reactions on Supported Metal Catalysts written by Megan Ingalls and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Organic modifiers can impact heterogeneous catalyst selectivity and activity by altering the adsorption preferences and surface reaction paths. Dually coated supported nanoparticle metal catalysts are prepared, with organic modifiers on both metal particles and their oxide support. Thiols are used to modify metals, with the sulfur head group binding to the surface, while phosphonic acids are used to modify the support. Both thiol and phosphonic acid modifiers form self-assembled monolayers (SAM) on the catalyst surface. Cinnamaldehyde hydrogenation was used to probe the performance of the as-prepared catalysts; the selectivity to cinnamyl alcohol could be potentially improved without significant decreases in activity by coating two self-assembled monolayers on the surface of the catalyst. For the dually coated catalyst, the thiol modifier mainly increased selectivity as was expected from previous work, while the phosphonate coating mainly increased the activity. When adding both thiols and phosphonates to the catalysts in different orders, it was found that the selectivity resembled the second SAM that was added to the catalyst. These changes in selectivity from the second SAM added to the surface were less drastic than the selectivity changes from a single SAM on the surface. For the activity of the catalyst, all of the catalysts with phosphonate coating showed increased activity for cinnamyl alcohol production in comparison to the uncoated Pt/Al2O3. The largest increase was seen when phosphonate was added after the thiol, likely from the thiol leaving open the selective active sites that favor cinnamyl alcohol production while the larger amount of phosphonate effected the electronic properties on the surface to increase the rate.A next potential step in this research is to use organic modifiers to tune the performance of single metal atom catalysts on oxide supports. As an initial step towards this goal, a computational model was developed to investigate hydrogenation reactions on a supported single metal atom catalyst. The catalyst modeled was a single Pt atom catalyst on the 101 surface of anatase TiO2. Acetaldehyde and trans-2-butene were used to model the functional groups in cinnamaldehyde that can be selectively hydrogenated. Multiple models were made to observe how the oxidation state of Pt0, Pt2+, and Pt4+ impacts hydrogenation reaction energies. In the Pt0 models, the adsorption of hydrogen to the surface for the reaction was unfavorable. The absence of hydrogen adsorbed to the surface would cause this catalyst to be unable to hydrogenate trans-2-butene or acetaldehyde. Both the Pt2+ and Pt4+ catalysts adsorbed hydrogen very strongly; however, this very low energy state that was created made it unfavorable for the hydrogen to leave the surface to hydrogenate the trans-2-butene and acetaldehyde.
Download or read book Catalysis by Materials with Well Defined Structures written by Zili Wu and published by Academic Press. This book was released on 2015-03-26 with total page 393 pages. Available in PDF, EPUB and Kindle. Book excerpt: Catalysis by Materials with Well-Defined Structures examines the latest developments in the use of model systems in fundamental catalytic science. A team of prominent experts provides authoritative, first-hand information, helping readers better understand heterogeneous catalysis by utilizing model catalysts based on uniformly nanostructured materials. The text addresses topics and issues related to material synthesis, characterization, catalytic reactions, surface chemistry, mechanism, and theoretical modeling, and features a comprehensive review of recent advances in catalytic studies on nanomaterials with well-defined structures, including nanoshaped metals and metal oxides, nanoclusters, and single sites in the areas of heterogeneous thermal catalysis, photocatalysis, and electrocatalysis. Users will find this book to be an invaluable, authoritative source of information for both the surface scientist and the catalysis practitioner - Outlines the importance of nanomaterials and their potential as catalysts - Provides detailed information on synthesis and characterization of nanomaterials with well-defined structures, relating surface activity to catalytic activity - Details how to establish the structure-catalysis relationship and how to reveal the surface chemistry and surface structure of catalysts - Offers examples on various in situ characterization instrumental techniques - Includes in-depth theoretical modeling utilizing advanced Density Functional Theory (DFT) methods
Download or read book Isocyanide Chemistry written by V. Nenajdenko and published by John Wiley & Sons. This book was released on 2012-06-04 with total page 615 pages. Available in PDF, EPUB and Kindle. Book excerpt: The efficacy of isocyanide reactions in the synthesis of natural or naturallike products has resulted in a renaissance of isocyanide chemistry. Now isocyanides are widely used in different branches of organic, inorganic, coordination, combinatorial and medicinal chemistry. This invaluable reference is the only book to cover the topic in such depth, presenting all aspects of synthetic isonitrile chemistry. The highly experienced and internationally renowned editor has brought together an equally distinguished team of authors who cover multicomponent reactions, isonitriles in total synthesis, isonitriles in polymer chemistry and much more.
Download or read book Plasma Catalysis written by Annemie Bogaerts and published by MDPI. This book was released on 2019-04-02 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma catalysis is gaining increasing interest for various gas conversion applications, such as CO2 conversion into value-added chemicals and fuels, N2 fixation for the synthesis of NH3 or NOx, methane conversion into higher hydrocarbons or oxygenates. It is also widely used for air pollution control (e.g., VOC remediation). Plasma catalysis allows thermodynamically difficult reactions to proceed at ambient pressure and temperature, due to activation of the gas molecules by energetic electrons created in the plasma. However, plasma is very reactive but not selective, and thus a catalyst is needed to improve the selectivity. In spite of the growing interest in plasma catalysis, the underlying mechanisms of the (possible) synergy between plasma and catalyst are not yet fully understood. Indeed, plasma catalysis is quite complicated, as the plasma will affect the catalyst and vice versa. Moreover, due to the reactive plasma environment, the most suitable catalysts will probably be different from thermal catalysts. More research is needed to better understand the plasma–catalyst interactions, in order to further improve the applications.
Download or read book Nanotechnology in Catalysis 3 written by Bing Zhou and published by Springer Science & Business Media. This book was released on 2007-09-05 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume continues the tradition formed in Nanotechnology in Catalysis 1 and 2. As with those books, this one is based upon an ACS symposium. Some of the most illustrious names in heterogeneous catalysis are among the contributors. The book covers: Design, synthesis, and control of catalysts at nanoscale; understanding of catalytic reaction at nanometer scale; characterization of nanomaterials as catalysts; nanoparticle metal or metal oxides catalysts; nanomaterials as catalyst supports; new catalytic applications of nanomaterials.
Download or read book Nanoinformatics written by Isao Tanaka and published by Springer. This book was released on 2018-01-15 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book brings out the state of the art on how informatics-based tools are used and expected to be used in nanomaterials research. There has been great progress in the area in which “big-data” generated by experiments or computations are fully utilized to accelerate discovery of new materials, key factors, and design rules. Data-intensive approaches play indispensable roles in advanced materials characterization. "Materials informatics" is the central paradigm in the new trend. "Nanoinformatics" is its essential subset, which focuses on nanostructures of materials such as surfaces, interfaces, dopants, and point defects, playing a critical role in determining materials properties. There have been significant advances in experimental and computational techniques to characterize individual atoms in nanostructures and to gain quantitative information. The collaboration of researchers in materials science and information science is growing actively and is creating a new trend in materials science and engineering.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1993 with total page 906 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiannual, with semiannual and annual indexes. References to all scientific and technical literature coming from DOE, its laboratories, energy centers, and contractors. Includes all works deriving from DOE, other related government-sponsored information, and foreign nonnuclear information. Arranged under 39 categories, e.g., Biomedical sciences, basic studies; Biomedical sciences, applied studies; Health and safety; and Fusion energy. Entry gives bibliographical information and abstract. Corporate, author, subject, report number indexes.
Download or read book Surface and Nanomolecular Catalysis written by Ryan Richards and published by CRC Press. This book was released on 2006-05-25 with total page 555 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using new instrumentation and experimental techniques that allow scientists to observe chemical reactions and molecular properties at the nanoscale, the authors of Surface and Nanomolecular Catalysis reveal new insights into the surface chemistry of catalysts and the reaction mechanisms that actually occur at a molecular level during catalys
