Download or read book Computational Characterisation of Gold Nanocluster Structures written by Andrew James Logsdail and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computational Characterisation of Gold Nanocluster Structures written by Andrew James Logsdail and published by Springer Science & Business Media. This book was released on 2013-08-31 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, Andrew Logsdail demonstrates that computational chemistry is a powerful tool in contemporary nanoscience, complementing experimental observations and helping guide future experiments. The aim of this particular PhD is to further our understanding of structural and compositional preferences in gold nanoparticles, as well as the compositional and chemical ordering preferences in bimetallic nanoalloys formed with other noble metals, such as palladium and platinum. Highlights include: calculations of the structural preferences and optical-response of gold nanoparticles and gold-containing nanoalloys; the design and implementation of novel numerical algorithms for the structural characterisation of gold nanoparticles from electron microscopy images; and electronic structure calculations investigating the interaction of gold nanoparticles with graphene and graphite substrates.The results presented here have significant implications for future research on the chemical and physical properties of gold-based nanoparticles and are of interest to many researchers working on experimental and theoretical aspects of nanoscience.
Download or read book Surface Chemistry Characterization and Control of the Electronic Structure of Gold Nanosystems written by Zachary Rhoden and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal nanoparticles (NPs) are valued in fields including biomedical imaging, chemical sensing, catalysis, and fundamental physics. Their utility often stems from their unique optical and electronic properties, but their broad applicability is due to their robust surface chemistry that allows a wide variety of ligands to be bound to them to tune stability, solubility, and reactivity. However, there has been little work focusing on linking these two aspects of nanoparticles, despite their importance. The lack of work, in part, stems from the significant challenges arising from the inherent dispersity within nanoparticle populations and complicated characterization techniques in which sample measurement can be difficult or provide limited information. The focus of this thesis is to refine the understanding of the structure-property relationship in gold nanosystems by improving the characterization of gold surfaces and by controlling gold nanoparticle properties through surface chemistry. This thesis reports the characterization of the gold-thiol surface, where thermal treatment of gold nanoparticles (AuNPs) volatilized gold and sulfur, which was collected and subsequently quantified by inductively coupled plasma mass spectrometry and atomic emission spectroscopy. It was found that the mass loss in these samples ranged from 0-30\% gold by mass, rather than purely from the thiol ligands, and that the level of gold desorption is related to the Au--S bond strength.This study calls into question the usefulness of thermogravimetric analysis as a characterization technique of gold nanosytems. Additionally, the influence of surface chemistry on the electronic structure of gold nanosystems has been probed using magnetic spectroscopies. First, electron spin resonance has been used to examine the perturbation to the superatomic structure of Au$_{25}$(SR)$_#x18;$ nanoclusters (NCs) by a series of alkanethiolate ligands in hexane and tetrahydrofuran solvents. It has been found that the nanocluster electronic is sensitive to surface chemistry, with the $g_x$ component of the electronic \textit{g}-factor shifting linearly towards the free electron \textit{g}-value, $g_e$, and the perturbation is large, given the minute changes in ligand identity. The changes are dissimilar to those seen in gold nanoparticles with similar surface chemistry, indicating that use of AuNCs as model systems for larger, metallic AuNPs should be reevaluated. Finally, Evans Method nuclear magnetic resonance spectroscopy has been used to probe the density of states (DOS) of gold nanoparticles protected by aromatic thiolate ligands. Aromatic ligands are a common tool for tuning the electronic structure of inorganic complexes, and this thesis reports their capability to alter the electronic structure of gold nanoparticles. The DOS of these nanoparticles increases with increasing electron withdrawing character of the aromatic ligands, and it has been found that trends in controlling the gold nanoparticle's DOS found with aromatic thiols cannot necessarily be compared to those found with aliphatic thiols. This work examines not only how surface chemistry influences the properties of nanosystems, but also the usefulness of model systems and naive assumptions about characterization techniques.
Download or read book Supramolecular Gold Chemistry written by Rodolphe Antoine and published by MDPI. This book was released on 2020-06-23 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is about supramolecular gold chemistry. This book provides a unique international forum aimed at covering a broad description of results involving the supramolecular chemistry of gold with a special focus on the gold–sulfur interface leading to hybrid materials ranging from gold–thiolate complexes to thiolate-protected gold nanoclusters and gold–thiolate supramolecular assemblies or nanoparticles. The role of thiolates on the structure and optical features of gold nanohybrid systems (ranging from plasmonic gold nanoparticles and fluorescent gold nanoclusters to self-assembled Au-containing thiolated coordination polymers) is highlighted in the 12 papers presented in this book.
Download or read book Computational Study of Metal Nanoclusters on Silicon and Oxide Surfaces written by Chin-Lung Kuo and published by . This book was released on 2005 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Synthesis of Gold and Zirconia Nanoparticles and Their Characterization written by Stephan Dankesreiter and published by Diplomica Verlag. This book was released on 2011 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of small and smallest particle is one of today's key features in modern science. The goal is to form materials with improved properties than their "classical" ancestors with just a fractional amount of raw material. However, the characterization of these particles is as important as their way of preparation. Different techniques with their origins in physics, inorganic, organic and physical chemistry have to be combined to reveal the secrets of this important field of science. This book gives a short overview of theoretical basics and synthesis methods to form and characterize gold and zirconia nanoparticles. Phenomenon like plasmon resonance self-assembly of surfactants and the different structures of ZnO2 are explained. Furthermore, analytical tools, like small angle X-ray scattering, X-ray powder diffraction and scanning electron microscopy are introduced. In addition, details on the synthesis of gold and zirconia nanoparticles are presented and are examined by the mentioned analytical and calorimetric methods.
Download or read book Gold Nanoparticles written by Mohammed Muzibur Rahman and published by BoD – Books on Demand. This book was released on 2019-02-13 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gold Nanoparticles - Reaching New Heights contains recent research on the preparation, characterization, fabrication, and potential of optical and biological applications of gold nanoparticles (AuNPs). It is promising novel research that has received a lot of interest over the last few decades. It covers advanced topics on optical, physical, medicinal, and biological applications of AuNPs. Development of green nanotechnology is generating the interest of researchers towards the synthesis of eco-friendly, safe, non-toxic applications, which can be used for manufacture at a large scale. These are simple, cost-effective, stable, enduring, and reproducible aqueous room temperature synthesis applications to obtain the self-assembly of AuNPs. This potentially unique work offers various approaches to R
Download or read book Gold Clusters Colloids and Nanoparticles I written by D. Michael P. Mingos and published by Springer. This book was released on 2014-09-27 with total page 287 pages. Available in PDF, EPUB and Kindle. Book excerpt: The series Structure and Bonding publishes critical reviews on topics of research concerned with chemical structure and bonding. The scope of the series spans the entire Periodic Table and addresses structure and bonding issues associated with all of the elements. It also focuses attention on new and developing areas of modern structural and theoretical chemistry such as nanostructures, molecular electronics, designed molecular solids, surfaces, metal clusters and supramolecular structures. Physical and spectroscopic techniques used to determine, examine and model structures fall within the purview of Structure and Bonding to the extent that the focus is on the scientific results obtained and not on specialist information concerning the techniques themselves. Issues associated with the development of bonding models and generalizations that illuminate the reactivity pathways and rates of chemical processes are also relevant. The individual volumes in the series are thematic. The goal of each volume is to give the reader, whether at a university or in industry, a comprehensive overview of an area where new insights are emerging that are of interest to a larger scientific audience. Thus 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 should be presented using selected examples to illustrate the principles discussed. A description of the physical basis of the experimental techniques that have been used to provide the primary data may also be appropriate, if it has not been covered in detail elsewhere. The coverage need not be exhaustive in data, but should rather be conceptual, concentrating on the new principles being developed that will allow the reader, who is not a specialist in the area covered, to understand the data presented. Discussion of possible future research directions in the area is welcomed. Review articles for the individual volumes are invited by the volume editors. Readership: research scientists at universities or in industry, graduate students Special offer For all customers who have a standing order to the print version of Structure and Bonding, we offer free access to the electronic volumes of the Series published in the current year via SpringerLink.
Download or read book Computational Modelling of Nanoparticles written by Stefan T. Bromley and published by Elsevier. This book was released on 2018-09-12 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational Modelling of Nanoparticles highlights recent advances in the power and versatility of computational modelling, experimental techniques, and how new progress has opened the door to a more detailed and comprehensive understanding of the world of nanomaterials. Nanoparticles, having dimensions of 100 nanometers or less, are increasingly being used in applications in medicine, materials and manufacturing, and energy. Spanning the smallest sub-nanometer nanoclusters to nanocrystals with diameters of 10s of nanometers, this book provides a state-of-the-art overview on how computational modelling can provide, often otherwise unobtainable, insights into nanoparticulate structure and properties. This comprehensive, single resource is ideal for researchers who want to start/improve their nanoparticle modelling efforts, learn what can be (and what cannot) achieved with computational modelling, and understand more clearly the value and details of computational modelling efforts in their area of research. Explores how computational modelling can be successfully applied at the nanoscale level Includes techniques for the computation modelling of different types of nanoclusters, including nanoalloy clusters, fullerines and Ligated and/or solvated nanoclusters Offers complete coverage of the use of computational modelling at the nanoscale, from characterization and processing, to applications
Download or read book Atomically Precise Metal Nanoclusters written by Zhikun Wu and published by Springer Nature. This book was released on 2022-06-01 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atomically precise metal nanocluster research has emerged as a new frontier. This book serves as an introduction to metal nanoclusters protected by ligands. The authors have summarized the synthesis principles and methods, the characterization methods and new physicochemical properties, and some potential applications. By pursuing atomic precision, such nanocluster materials provide unprecedented opportunities for establishing precise relationships between the atomic-level structures and the properties. The book should be accessible to senior undergraduate and graduate students, researchers in various fields (e.g., chemistry, physics, materials, biomedicine, and engineering), R&D scientists, and science policy makers.
Download or read book Soft Computing in Chemical and Physical Sciences written by Kanchan Sarkar and published by CRC Press. This book was released on 2017-11-06 with total page 429 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book can be regarded as 'Soft computing for physicists and chemists self-taught'. It prepares the readers with a solid background of soft computing and how to adapt soft computing techniques to problem solving in physical and chemical research. Soft computing methods have been little explored by researchers in physical and chemical sciences primarily because of the absence of books that bridge the gap between the traditional computing paradigm pursued by researchers in science and the new soft computing paradigm that has emerged in computer science. This book is the interface between these primary sources and researchers in physics and chemistry.
Download or read book Quantitative Computational and Experimental Characterization of Functionalized Nanoparticles written by Yung-Chen Wang and published by . This book was released on 2017 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanoparticles are widely used in many fields of science and can often be found in everyday commercial products. This widespread use of nanoparticles in our daily lives and the industry have raised several concerns regarding the safety and environmental impact of these nanoparticles. In the biomedical field, understanding how nanoparticles interact with the biological environment is crucial for public safety and advancing the development of nanomedicine. In this work, both computational and experimental methods were developed to aid the surface chemical characterization of functionalized nanoparticles. The major experimental project focuses on controlling and probing the orientation of immobilized proteins on gold nanoparticles. Protein G B1, a protein that will selectively bind to the Fc region of IgG, was immobilized onto gold NPs (AuNPs) functionalized with oligo(ethylene glycol)-Maleimide (OEG-MEG) self-assembled monolayers (SAMs). The orientation of the protein can be controlled via a site-specific maleimide-sulfhydryl reaction between the OEG-MEG SAMs and the cysteine amino acid in the protein. Utilizing site-specific chemistry and surface sensitive analysis techniques of X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS), it was possible to both control and determine the orientation of immobilized Protein G B1on gold nanoparticles. In addition to experimental analysis, robust computer simulations using the Simulation of Electron Spectra for Surface Analysis (SESSA) program were incorporated to aid the characterization of a wide variety of nanoparticles. It was demonstrated that SESSA can accurately simulate XPS spectra and peak intensities of nanoparticles and verify existing methods of calculating overlayer thickness of core-shell nanoparticles. Further, SESSA can be applied to assess the structure and thickness of various SAMs on both flat and nanoparticle surfaces by incorporating experimentally collected XPS and sum-frequency generation (SFG) results. In another study, SESSA was applied to model citrate stabilized Au/Ag-core/shell nanoparticles with complex geometrical properties. The Au/Ag-core/shell NPs were polydispersed in size, non-spherical, and contained off-centered Au-cores. The NPs were characterized using XPS and scanning transmission electron microscopy (STEM) to determine the composition and morphology of the NPs. Simulating NPs with average dimensions and not accounting for the geometrical properties of the NPs resulted in significant underestimation of the gold intensity. Simulations based on the combined effect of NP non-sphericity and off-centered Au-core resulted in reduced effective Ag-shell thickness and provided simulated elemental compositions that matched the experimental XPS results.
Download or read book A Computational Study of Small Gold Clusters H2S Thiols H2O and Alcohols written by Silvija C. Smith and published by . This book was released on 2014 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bulk gold is known to be one of the least reactive metals. In contrast, gold colloids and gold nanoclusters exhibit unique chemical and physical properties, due to their stability, uniformity, and size related characteristics. These interesting attributes cause gold nanoclusters to have promising applications in catalysis, biosensors, and optoelectronics. In particular, many of the applications for gold nanoclusters are in the fields of biomedicine and biotechnology. These potential applications require aggregation resistant, water-soluble nanoparticles capable of withstanding an environment within living organisms. Additionally, previous studies have shown that supported gold nanoclusters can be used as catalysts for many hydrogenation and oxidation reactions at low temperatures. These reactions include the oxidation of carbon monoxide (CO) and nitric oxide (NO), partial oxidation of propylene, and partial and complete hydrogenation of acetylene and ethylene, respectively. In this thesis, density functional theory (DFT) calculations are used to obtain energies of equilibrium structures from geometry optimizations and vibrational frequencies of small gold clusters, with one to four gold atoms bonded to a water molecule, small alcohols, or short-chain thiols, SHR, wth R=H, CH 3, CH3 CH2 . Additionally, density functional theory, Moller-Plesset Perturbation theory, and coupled cluster theory calculations were used to obtain energies, optimal geometries, vibrational frequencies, activation energies, and the rate of reaction for the hydrogen atom transfer from sulphur to gold of the RSH-Au n and RSAun H complexes. These complexes consist of small gold clusters, with n=1-4 and short-chain thiols wth R=H, CH3, and CH3 CH2. The Gibbs free energies were calculated to determine whether the hydrogen atom transfer occurs as a thermodynamically spontaneous reaction. Additionally, common trends of the cluster complexes including bond lengths and characteristic gold-sulphur and gold-oxygen vibrational stretching were examined. Depending on the ligand attached to the gold cluster and the overall charge of the complex, bridge-bonding to different pairs of gold atoms in the cluster can occur with the hydrogen atom that has been transferred and the sulphur atom or oxygen atom. These theoretical studies are used to expand on the limited understanding of gold clusters and their interesting characteristics. Additionally, these studies determine the versatility of various basis functionals and basis sets when used on many electron atoms, such as gold. The results from this study are compared to similar studies involving gold clusters.
Download or read book International Conference on Computing Communication Electrical and Biomedical Systems written by Arulmurugan Ramu and published by Springer Nature. This book was released on 2022-02-28 with total page 673 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents selected papers from the International Conference on Computing, Communication, Electrical and Biomedical Systems (ICCCEBS 2021), held in March 2021 at KPR College of Engineering and Technology, Coimbatore, Tamil Nadu, India. The conference explores the interface between industry and real-time environments with newly developed techniques in computing and communications engineering. The papers describe results of conceptual, constructive, empirical, experimental, and theoretical work in areas of computing, communication, electrical, and biomedical systems. Contributors include academic scientists, researchers, industry representatives, postdoctoral fellows, and research scholars from around the world.
Download or read book Synthesis and Characterisation of Gold Nanoclusters for Catalysis Applications written by Maria Leonor Rodrigues Alves and published by . This book was released on 2014 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: Esta tesis doctoral trata sobre la síntesis, y el estudio de la actividad catalítica de partículas de oro de tamaño inferior a 2 nm, nanoclústers de oro. El interés proviene de la actividad catalítica a temperatura ambiente que tiene el oro cuando las dimensiones son inferiores a aproximadamente los 5 nm. En esta tesis se desarrollan dos métodos de síntesis que permiten obtener clústeres de oro estables con un tamaño de partícula bien definido. En un método se sintetizan nanoclústeres de oro de tamaño inferior a 2 nm, los cuales son posteriormente depositados sobre un soporte. En cambio, el otro método consiste en sintetizar los nanoclústeres de oro directamente sobre el soporte seleccionado. Con este ultimo método, se puede modificar el tamaño de los clústeres de oro alterando la cantidad de precursor de oro durante el proceso de síntesis. De esta manera se puede obtener desde una dispersión uniforme de átomos de oro aislados, clústeres de Au de 2 nm o nanopartículas de más de 10 nm en la superficie del material de soporte. Los catalizadores sintetizados han sido caracterizados mediante distintas técnicas físico químicas: HRTEM, SEM, AFM, XPS and XAS. Además también se ha estudiado la actividad catalítica para la oxidación de CO y materiales carbonosos. Finalmente, se ha relacionado el tamaño de partícula con la actividad catalítica del material.
Download or read book Gold Nanoparticles For Physics Chemistry And Biology Second Edition written by Catherine Louis and published by World Scientific. This book was released on 2017-06-02 with total page 681 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gold Nanoparticles for Physics, Chemistry and Biology offers an overview of recent research into gold nanoparticles, covering their discovery, usage and contemporary practical applications.This Second Edition begins with a history of over 2000 years of the use of gold nanoparticles, with a review of the specific properties which make gold unique. Updated chapters include gold nanoparticle preparation methods, their plasmon resonance and thermo-optical properties, their catalytic properties and their future technological applications. New chapters have been included, and reveal the growing impact of plasmonics in research, with an introduction to quantum plasmonics, plasmon assisted catalysis and electro-photon conversion. The growing field of nanoparticles for health is also addressed with a study of gold nanoparticles as radiosensibiliser for radiotherapy, and of gold nanoparticle functionalisation. This new edition also considers the relevance of bimetallic nanoparticles for specific applications.World-class scientists provide the most up-to-date findings for an introduction to gold nanoparticles within the related areas of chemistry, biology, material science, optics and physics. It is perfectly suited to advanced level students and researchers looking to enhance their knowledge in the study of gold nanoparticles.
Download or read book Gold Nanoparticles written by P. E. Chow and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to their attractive electronic, optical, and thermal properties; gold nanoparticles (AuNPs) have emerged with great interest, as well as catalytic properties, in the fields of physics, chemistry, biology, medicine, material science and some interdisciplinary fields. This book examines a broad range of applications of gold nanoparticles such as: gold nanoparticles as an antigen carrier and as an adjuvant; laser synthesis of gold nanoparticles and the control over their properties; gold on carbon catalysts; gold nanoparticles as a delivery vehicle in biomedical applications; solution and solid-state methods to prepare Au nanoparticles; gold nanoparticles and their in-vitro property, the usefulness of gold nanoparticles in emerging infectious disease situations and a host of others.
