Download or read book Surface Chemistry of Metal Catalyst Under Carbon Nanotube Growth Conditions written by Tyson Cody Back and published by . This book was released on 2010 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: The catalyst nanoparticle is critical to the yield, type, and diameter in the growth and nucleation of carbon nanotubes. The objective of this study is focused on determining what changes take place with the catalyst chemistry under growth conditions typically seen in chemical vapor deposition, CVD, experiments. It is well known that catalyst poisoning can occur and in turn effects the catalytic activity of the nanoparticle. A complete description of this mechanism is as of yet undetermined. In order to elucidate this process iron films were deposited onto Si substrates that contained a support layer of Al2O3 or SiO2. These samples were investigated with various surface chemistry techniques such as X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), and electron energy loss spectroscopy (EELS). In addition, structural characteristics were investigated with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The surface techniques were used in-situ in order to observe chemistries that might not be observable outside a CVD reactor. Two sets of experiments were performed on the silica and alumina supports. The first consisted of carbon nanotube growth at near atmospheric pressure, while the second was performed under vacuum. The oxide support was shown to have an affect on the type of nanotubes grown under identical conditions. The silica support films produced more MWNT, while the alumina support films produced more SWNT. This difference was due to the amount of ripening that takes place on the oxide supports. Also in-situ XPS revealed differences in the chemistry of iron catalyst during growth and these differences were attributed to substrate interactions between alumina and iron. Finally, in-situ XPS analysis showed no evidence of carbides or oxides acting as a catalyst during the nucleation process.

Download or read book Carbon Nanotube Materials for Substrate Enhanced Control of Catalytic Activity written by and published by . This book was released on 2007 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon SWNTs are attractive materials for supporting electrocatalysts. The properties of SWNTs are highly tunable and controlled by the nanotube's circumferential periodicity and their surface chemistry. These unique characteristics suggest that architectures constructed from these types of carbon support materials would exhibit interesting and useful properties. Here, we expect that the structure of the carbon nanotube support will play a major role in stabilizing metal electrocatalysts under extreme operating conditions and suppress both catalyst and support degradation. Furthermore, the chemical modification of the carbon nanotube surfaces can be expected to alter the interface between the catalyst and support, thus, enhancing the activity and utilization of the electrocatalysts. We plan to incorporate discrete reaction sites into the carbon nanotube lattice to create intimate electrical contacts with the catalyst particles to increase the metal catalyst activity and utilization. The work involves materials synthesis, design of electrode architectures on the nanoscale, control of the electronic, ionic, and mass fluxes, and use of advanced optical spectroscopy techniques.

Download or read book Synthesis and Applications of Nanocarbons written by Jean-Charles Arnault and published by John Wiley & Sons. This book was released on 2020-09-21 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: A crucial overview of the cutting-edge in nanocarbon research and applications In Synthesis and Applications of Nanocarbons, the distinguished authors have set out to discuss fundamental topics, synthetic approaches, materials challenges, and various applications of this rapidly developing technology. Nanocarbons have recently emerged as a promising material for chemical, energy, environmental, and medical applications because of their unique chemical properties and their rich surface chemistries. This book is the latest entry in the Wiley book series Nanocarbon Chemistry and Interfaces and seeks to comprehensively address many of the newly surfacing areas of controversy and development in the field. This book introduces foundational concepts in nanocarbon technology, hybrids, and applications, while also covering the most recent and cutting-edge developments in this area of study. Synthesis and Applications of Nanocarbons addresses new discoveries in the field, including: · Nanodiamonds · Onion-like carbons · Carbon nanotubes · Fullerenes · Carbon dots · Carbon fibers · Graphene · Aerographite This book provides a transversal view of the various nanocarbon materials and hybrids and helps to share knowledge between the communities of each material and hybrid type.

Download or read book Single Walled Carbon Nanotubes written by Yan Li and published by Springer. This book was released on 2019-05-16 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: The series Topics in Current Chemistry Collections presents critical reviews from the journal Topics in Current Chemistry organized in topical volumes. The scope of coverage is all areas of chemical science including the interfaces with related disciplines such as biology, medicine and materials science. The goal of each thematic volume is to give the non-specialist reader, whether in academia or industry, a comprehensive insight into an area where new research is emerging which is of interest to a larger scientific audience. Each review within the volume critically surveys one aspect of that topic and places it within the context of the volume as a whole. The most significant developments of the last 5 to 10 years are presented using selected examples to illustrate the principles discussed. The coverage is not intended to be an exhaustive summary of the field or include large quantities of data, but should rather be conceptual, concentrating on the methodological thinking that will allow the non-specialist reader to understand the information presented. Contributions also offer an outlook on potential future developments in the field.

Download or read book Metal Nanoparticles for Catalysis written by Franklin Tao and published by Royal Society of Chemistry. This book was released on 2014-06-12 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: Catalysis is a central topic in chemical transformation and energy conversion. Thanks to the spectacular achievements of colloidal chemistry and the synthesis of nanomaterials over the last two decades, there have also been significant advances in nanoparticle catalysis. Catalysis on different metal nanostructures with well-defined structures and composition has been extensively studied. Metal nanocrystals synthesized with colloidal chemistry exhibit different catalytic performances in contrast to metal nanoparticles prepared with impregnation or deposition precipitation. Additionally, theoretical approaches in predicting catalysis performance and understanding catalytic mechanism on these metal nanocatalysts have made significant progress. Metal Nanoparticles for Catalysis is a comprehensive text on catalysis on Nanoparticles, looking at both their synthesis and applications. Chapter topics include nanoreactor catalysis; Pd nanoparticles in C-C coupling reactions; metal salt-based gold nanocatalysts; theoretical insights into metal nanocatalysts; and nanoparticle mediated clock reaction. This book bridges the gap between nanomaterials synthesis and characterization, and catalysis. As such, this text will be a valuable resource for postgraduate students and researchers in these exciting fields.

Download or read book Carbon Nanotube and Related Field Emitters written by Yahachi Saito and published by John Wiley & Sons. This book was released on 2010-10-01 with total page 551 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon nanotubes (CNTs) have novel properties that make them potentially useful in many applications in nanotechnology, electronics, optics and other fields of materials science. These characteristics include extraordinary strength, unique electrical properties, and the fact that they are efficient heat conductors. Field emission is the emission of electrons from the surface of a condensed phase into another phase due to the presence of high electric fields. CNT field emitters are expected to make a breakthrough in the development of field emission display technology and enable miniature X-ray sources that will find a wide variety of applications in electronic devices, industry, and medical and security examinations. This first monograph on the topic covers all aspects in a concise yet comprehensive manner - from the fundamentals to applications. Divided into four sections, the first part discusses the preparation and characterization of carbon nanotubes, while part two is devoted to the field emission properties of carbon nanotubes, including the electron emission mechanism, characteristics of CNT electron sources, and dynamic behavior of CNTs during operation. Part three highlights field emission from other nanomaterials, such as carbon nanowalls, diamond, and silicon and zinc oxide nanowires, before concluding with frontier R&D applications of CNT emitters, from vacuum electronic devices such as field emission displays, to electron sources in electron microscopes, X-ray sources, and microwave amplifiers. Edited by a pioneer in the field, each chapter is written by recognized experts in the respective fields.

Download or read book Rational Catalyst Design for Carbon Nanotube Carpet Growth and Fischer Tropsch Synthesis written by Xu Li and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The first part of this research involves the growth of vertically aligned carbon nanotube (CNT) arrays (or CNT carpets) that are desired in many important applications. Growth of high-quality, dense CNT carpets via catalytic chemical vapor deposition (CCVD) has been largely limited to catalysts supported on amorphous alumina or silica. Although catalyst design and CCVD process optimization have been extensively investigated, scalable growth of CNT carpets especially on nontraditional substrates remains largely a challenge. To develop a rational basis for designing efficient CNT catalysts, a deeper understanding of the role of substrates in CNT carpet growth during CCVD is required. In this study, a fundamental investigation of the effects of substrate properties on CNT carpet growth from supported catalysts under different reaction conditions and feedstock is carried out. To illuminate the interrelationships between properties of catalyst supporting layers on CNT carpet growth behaviors, CNT growth experiments from Fe catalyst supported on a variety of nontraditional substrates including stainless steel (SS), MgO, MgAl2O4 (100, 110, and 111 crystalline phases), and ZrO2 were carried out. This study reveals that ion beam bombardment of 316 SS decreases the film thickness of AlxOy required for CNT growth to 5 nm AlxOy. The role of ion beam bombardment is to transform a highly crystalline surface into an amorphous surface, resulting in favorable catalyst-substrate interactions that enhances CNT growth. Our results reveal that Fe catalyst supported on different phases of MgAl2O4 spinel substrates show different CNT growth behaviors due to their different surface chemistries and surface energies. The second part of this research is motivated by the drive to seek new routes that yield clean fuels and chemicals via Fischer-Tropsch synthesis (FTS). FTS provides a pathway for the transformation of biomass, coal or natural gas into fuels and chemicals using a transition metal catalyst. Co-based catalysts are of interest because they exhibit relatively higher activity and selectivity to long-chain paraffins, high resistance to deactivation, and a low water-gas shift (WGS) reaction activity. Catalytic performance is sensitive to the catalyst preparation method and type of catalyst precursor. To investigate the effect of the type of catalyst precursor used during synthesis on physicochemical properties and efficiency of FTS process, SiO2-supported Co catalysts were synthesized via an incipient wetness impregnation method from four different precursors: Co(NO3)2 (Co-Nit), Co(C2H3O2)2 (Co-Ace), CoCl2 (Co-Chl), and Co(OH)2 (Co-Hyd). This study reveals the type of Co precursor used during synthesis has significant effects on catalyst dispersion, size, crystalline phase, reducibility, stability, and FTS performance (CO conversion, C5+ selectivity, turnover frequency, and catalyst lifetime). Prenatal and postmortem characterization of the catalyst reveal sintering and formation of Co2C in all catalysts except Co-Nit, which may explain the various degrees of deactivation observed. Further, XANES and EXAFS data confirm the superior structural stability of Co-Hyd and presence of hydroxyl groups even after reaction.

Download or read book Frontiers in Surface Science and Interface Science written by C.B. Duke and published by Gulf Professional Publishing. This book was released on 2002-05-21 with total page 1076 pages. Available in PDF, EPUB and Kindle. Book excerpt: Any notion that surface science is all about semiconductors and coatings is laid to rest by this encyclopedic publication: Bioengineered interfaces in medicine, interstellar dust, DNA computation, conducting polymers, the surfaces of atomic nuclei - all are brought up to date. Frontiers in Surface and Interface Science - a milestone publication deserving a wide readership. It combines a sweeping expert survey of research today with an educated look into the future. It is a future that embraces surface phenomena on scales from the subatomic to the galactic, as well as traditional topics like semiconductor design, catalysis, and surface processing, modeling and characterization. And, great efforts have been made to express sophisticated ideas in an attractive and accessible way. Nanotechnology, surfaces for DNA computation, polymer-based electronics, soft surfaces, interstellar surface chemistry - all feature in this comprehensive collection.

Download or read book Carbon Nanotubes From Basic Research to Nanotechnology written by Valentin N. Popov and published by Springer Science & Business Media. This book was released on 2006-05-03 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is about 15 years that the carbon nanotubes have been discovered by Sumio Iijima in a transmission electron microscope. Since that time, these long hollow cylindrical carbon molecules have revealed being remarkable nanostructures for several aspects. They are composed of just one element, Carbon, and are easily produced by several techniques. A nanotube can bend easily but still is very robust. The nanotubes can be manipulated and contacted to external electrodes. Their diameter is in the nanometer range, whereas their length may exceed several micrometers, if not several millimeters. In diameter, the nanotubes behave like molecules with quantized energy levels, while in length, they behave like a crystal with a continuous distribution of momenta. Depending on its exact atomic structure, a single-wall nanotube –that is to say a nanotube composed of just one rolled-up graphene sheet– may be either a metal or a semiconductor. The nanotubes can carry a large electric current, they are also good thermal conductors. It is not surprising, then, that many applications have been proposed for the nanotubes. At the time of writing, one of their most promising applications is their ability to emit electrons when subjected to an external electric field. Carbon nanotubes can do so in normal vacuum conditions with a reasonable voltage threshold, which make them suitable for cold-cathode devices.

Download or read book Nanostructured Carbon Materials for Catalysis written by Philippe Serp and published by Royal Society of Chemistry. This book was released on 2015 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt: Looking at the structure, properties and synthesis of nanocarbons as catalysts, this is the first book to provide a comprehensive view of the subject.

Download or read book Graphene Science Handbook written by Mahmood Aliofkhazraei and published by CRC Press. This book was released on 2016-04-21 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt: Examines the Low Resistivity, High Mobility, and Zero Bandgap of GrapheneThe Graphene Science Handbook is a six-volume set that describes graphene's special structural, electrical, and chemical properties. The book considers how these properties can be used in different applications (including the development of batteries, fuel cells, photovoltaic

Download or read book Nanostructured Catalysts for Environmental Applications written by Marco Piumetti and published by Springer Nature. This book was released on 2021-01-20 with total page 435 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers an overview of the recent studies and advances in environmental catalysis by nanomaterials, considering both the fundamental and the technological aspects. It offers contributions in different areas of environmental catalysis, including the catalytic and photocatalytic abatement of environmentally hazardous effluents from stationary or mobile sources, the valorization of waste and the production of sustainable energy. In other words, this monograph provides an overview of modern environmental and energy related applications with a particular emphasis to nano-sized catalytic materials. Recent concepts, experimental data and advanced theories are reported in this book to give evidence of the environmental and sustainable applications that can be found in the highly interdisciplinary field of catalysis.

Download or read book Carbon Allotropes Metal Complex Chemistry Properties and Applications written by Boris Ildusovich Kharisov and published by Springer. This book was released on 2019-01-02 with total page 790 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a detailed description of metal-complex functionalized carbon allotrope forms, including classic (such as graphite), rare (such as M- or T-carbon), and nanoforms (such as carbon nanotubes, nanodiamonds, etc.). Filling a void in the nanotechnology literature, the book presents chapters generalizing the synthesis, structure, properties, and applications of all known carbon allotropes. Metal-complex composites of carbons are described, along with several examples of their preparation and characterization, soluble metal-complex carbon composites, cost-benefit data, metal complexes as precursors of carbon allotropes, and applications. A lab manual on the synthesis and characterization of carbon allotropes and their metal-complex composites is included. Provides a complete description of all carbon allotropes, both classic and rare, as well as carbon nanostructures and their metal-complex composites; Contains a laboratory manual of experiments on the synthesis and characterization of metal-complex carbon composites; Discusses applications in diverse fields, such as catalysis on supporting materials, water treatment, sensors, drug delivery, and devices.

Download or read book Carbon Nanotubes written by Michael J. O’Connell and published by CRC Press. This book was released on 2018-10-03 with total page 339 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since their discovery more than a decade ago, carbon nanotubes (CNTs) have held scientists and engineers in captive fascination, seated on the verge of enormous breakthroughs in areas such as medicine, electronics, and materials science, to name but a few. Taking a broad look at CNTs and the tools used to study them, Carbon Nanotubes: Properties and Applications comprises the efforts of leading nanotube researchers led by Michael O’Connell, protégé of the late father of nanotechnology, Richard Smalley. Each chapter is a self-contained treatise on various aspects of CNT synthesis, characterization, modification, and applications. The book opens with a general introduction to the basic characteristics and the history of CNTs, followed by discussions on synthesis methods and the growth of “peapod” structures. Coverage then moves to electronic properties and band structures of single-wall nanotubes (SWNTs), magnetic properties, Raman spectroscopy of electronic and chemical behavior, and electromechanical properties and applications in NEMS (nanoelectromechanical systems). Turning to applications, the final sections of the book explore mechanical properties of SWNTs spun into fibers, sidewall functionalization in composites, and using SWNTs as tips for scanning probe microscopes. Taking a fresh look at this burgeoning field, Carbon Nanotubes: Properties and Applications points the way toward making CNTs commercially viable.

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

Download or read book Engineering Catalytic Activity Via Ion Beam Bombardment of Catalyst Supports for Vertically Aligned Carbon Nanotube Growth written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon nanotube growth depends on the catalytic activity of metal nanoparticles on alumina or silica supports. The control on catalytic activity is generally achieved by variations in water concentration, carbon feed, and sample placement on a few types of alumina or silica catalyst supports obtained via thin film deposition. We have recently expanded the choice of catalyst supports by engineering inactive substrates like c-cut sapphire via ion beam bombardment. The deterministic control on the structure and chemistry of catalyst supports obtained by tuning the degree of beam-induced damage have enabled better regulation of the activity of Fe catalysts only in the ion beam bombarded areas and hence enabled controllable super growth of carbon nanotubes. A wide range of surface characterization techniques were used to monitor the catalytically active surface engineered via ion beam bombardment. The proposed method offers a versatile way to control carbon nanotube growth in patterned areas and also enhances the current understanding of the growth process. As a result, with the right choice of water concentration, carbon feed and sample placement, engineered catalyst supports may extend the carbon nanotube growth yield to a level that is even higher than the ones reported here, and thus offers promising applications of carbon nanotubes in electronics, heat exchanger, and energy storage.

Download or read book Hydrogen Materials Science and Chemistry of Metal Hydrides written by T. Nejat Veziroglu and published by Springer Science & Business Media. This book was released on 2002-10-31 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 2001 International Conference «Hydrogen Materials Science and Chemistry of Metal Hydrides» (ICHMS'2001) was held in the picturesque town Alushta (Crimea, Ukraine) on the bank of Black Sea in September 16-22, 2001. In the tradition of the earlier ICHMS conferences, the 7th ICHMS'2001 provided an international forum for the presentation and discussion of the latest research on transition to hydrogen-based energy systems, technologies for hydrogen production, storage, utilization, materials, energy and environmental problems. The aim of ICHMS '200 1 was to provide an overview of the latest information on research and development in the different topics cited above. The representatives from industry, public laboratories, universities and governmental agencies could meet, discuss and present the most recent advances in hydrogen concepts, processes and systems, to evaluate current progress in these areas of investigations and to identify promising research directions for the future. The ICHMS'2001 was the first conference in this series, where a related new important topic of considerable current interest on fullerene-related materials as hydrogen storage was included into the conference program. The hydrogen sorbing properties of newly discovered carbon nanostructural materials inspire hydrogen scientists with optimism. Thus, the ICHMS'2001 conference was unique in bringing together hydrogen and carbon materials researchers and engineers from developed countries of Europe and America, new independent states of FSU and other countries for discussions in advanced materials development and applications.