bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carbon Nanotubes: Fluorinated Derivatives
Authors: Khabashesku Valery N. , Kuznetsov Oleksandr V. , Pulikkathara Merlyn X. 
Published: March 2009

AbstractOngoing extensive research on carbon nanotubes (CNTs) has been facilitated by unique physicochemical properties and wide opportunities the CNTs offer for the new field of nanotechnology. Recent studies have shown that for efficient use of the remarkable properties of CNTs, particularly in the design of multifunctional materials for engineering and biomedical applications, they need to be surface modified by attachment of functional groups for improving solubility, processing, and compatability with host materials. It has been shown that fluorination is an efficient way to modify and control the surface properties of CNTs. For instance, fluorine functional groups on the sidewalls of CNTs effectively assist in unroping the nanotube bundles and in dispersion in alcohols and other polar solvents. Weakness of the CF bond and solubility of fluorinated nanotubes (fluoronanotubes) provide an opportunity for the synthesis of a variety of nanotube derivatives by substitution of fluorine through wet chemistry methods. This approach has been applied to preparation of a series of amino, amide, hydroxyl, thiol, and carboxyl group‐terminated derivatives. The activated sidewall CC π bonds in fluoronanotubes also permit a solution‐phase chemistry leading to addition reactions of free radicals, carbenes, dienes, and other reactive molecules. Functional groups chemically attached to the CNTs effectively assist in the dispersion of CNTs in polymer matrices, crucial for nanocomposites fabrication. “Tailored” chemical modifications are particularly useful for creating multiple sites for covalent bonding of nanotubes to polymer matrices for the enhancement of mechanical properties of epoxy, polyethylene, polypropylene, and nylon. Fluorinated CNTs represent a new family of nanoscale fluorocarbon materials. They enable various applications of functionalized CNTs, derived from fluoronanotubes, particularly in nanocomposites, sensors, nanoelectronic devices, nanoengineered drug delivery systems, and nanolubricants.
Carbon Nanotubes, Multi‐Walled
Authors: Andrews Rodney , Weisenberger Matthew C. , Qian Dali , Meier Mark S. , Cassity Kelby , Yeary Paul E. 
Published: March 2009

AbstractWell‐aligned carbon multiwalled nanotubes (MWNTs) have been synthesized continuously by pyrolysis of xylene–ferrocene mixtures. To study the MWNT growth mechanism, two‐step processes and various chemical vapor deposition (CVD) parameters have been employed. Transmission electron microscopy observations support a tip‐root growth model of MWNTs by floating catalytic CVD. Hydrocarbon analyzer is used to measure the total carbon balance within the CVD reactor, while mass spectra analyses monitor the concentrations of hydrocarbon species, which helps to understand the catalyst deactivation and pyrolysis chemistry of xylene over catalyst Fe(C) nanoparticles. MWNTs can be treated to attach required functional groups on nanotube walls and/or caps for specific applications by various methods including acid oxidation, reduction, addition of radicals, and cycloadditions. Carbon nanotubes (CNTs) have shown promising applications in advanced CNT–polymer composites. To realize CNT potentials to enhance the properties of matrices, several important issues such as dispersion, orientation, interfacial effects, and processing parameters have been addressed. The dependence of the CNT–polymer composite properties on CNT diameter, length, and interfacial effects has been used to develop models to predict and optimize variables for maximum composite performance. CNT–polymer composites have been developed for enhanced mechanical, electrical, and thermal properties, which have wide applications for the next generation of truly multifunctional materials as well as lighter weights and increased manufacturability over current materials.
Liquid‐Phase Synthesis of Inorganic Nanoparticles
Authors: Caruntu Gabriel , Caruntu Daniela , O'Connor Charles J. 
Published: March 2009

AbstractIn this article we review some of the most representative liquid‐phase synthetic methodologies for the preparation of inorganic nanoparticles. Metallic nanoparticles and alloys have been chosen as a model to discuss the preparation of colloidal nanocrystals and their functionalization with organic molecules. Of a particular interest have been the synthetic methodologies allowing not only the compositional control of the nanoparticles but also the size/shape of the nanoparticles along with their ability to organize into hierarchical architectures suitable for different technological applications.
Gold Nanoparticles: Monolayer‐Protected Scaffolds and Building Blocks
Authors: Ofir Yuval , Srivastava Sudhanshu , Rotello Vincent M. 
Published: March 2009

Abstract
Nanoparticles provide key tools for bridging the gap between “bottom‐up” synthetic methods and “top‐down” fabrication. In this article, we describe recent progress in the recognition‐mediated assembly of metal nanoparticles using small molecules and polymers. A significant portion of the article focuses on the interaction of nanoparticles with biological moieties such as peptides and proteins, and the use of nanoparticles as drug and gene carriers for application in biomedical applications.
Nano/Microporous Materials: Crystalline Metal‐Chalcogenide Superlattices
Authors: Lin Zhien , Feng Pingyun , Bu Xianhui 
Published: March 2009

AbstractThis article describes the recent research progress in the field of crystalline metal‐chalcogenide superlattices containing tetrahedron‐shaped nanoclusters as building units. With the development of new synthetic strategies and structural concepts, new clusters that are members of three series of tetrahedral clusters (i.e., supertetrahedral clusters, pentasupertetrahedral clusters, and capped supertetrahedral clusters) have been prepared and organized into extended frameworks with a variety of topologies, such as single diamond, double diamond, ABW, CrB4, SOD, cubic C3N4, UCR‐1, ICF‐24, ICF‐25, α‐ and β‐quartz, moganite, and boracite. These materials show rich compositional diversities with tunable optical properties, microporosity, and ion‐exchange properties, suggesting their potential applications in photocatalysis, fast‐ion conductors, solar cells, etc.
Nanocomposite Materials: Polyhedral Silsesquioxanes
Authors: Seifalian Alexander M. , Kannan Ruben Y. , Ghanbari Hossein , Bakhshi Raheleh 
Published: March 2009

AbstractThe unique properties of nanocomposites have revolutionized the field of materials science. Polyhedral oligomeric silsesquioxane (POSS) is one of the widely used nanostructured materials for the synthesis of hybrid nanocomposites. POSS nanocrystals have been incorporated as building blocks of controllable shapes into polymers to form hybrid materials exhibiting improved properties. A variety of polymerization techniques have been used in the preparation of POSS‐containing hybrids. Incorporation of POSS into polymers can result in substantial improvement in physical properties of the polymers, such as low dielectric constants, increased glass‐transition temperatures, low coefficient of thermal expansion, enhanced thermal stability, mechanical strength, as well as improved oxidation resistance and reduction in flammability, oxygen permeability, heat evolution, and viscosity during processing. The most interesting POSS‐polymer has been the development of POSS–poly(carbonate‐urea)urethane that is used in medical applications owing to its enhanced biocompatibility and antithrombogenesity. These composites are materials of choice in the fabrication of various cardiovascular devices, such as artificial heart valves, stent‐grafts, bypass grafts, microvascular beds, and other biomedical devices including breast implants, and as scaffolds for tissue engineering.
Nanocomposite Materials: Semiconductors in Zeolites
Authors: Goldbach Andreas , Saboungi Marie‐Louise 
Published: March 2009

Abstract
Encapsulation in zeolites holds considerable promise for organizing semiconductor quantum dots and quantum wires into ordered two‐ and three‐dimensional arrays that can be used in a variety of applications. While the use of such materials has been limited until now by a number of practical difficulties, considerable progress has been made in the last few years in surmounting these obstacles. This article reviews recent progress in the field, particularly with regard to stabilization of the nanocomposites against moisture, modulation of their properties by appropriate cation substitution, and preparation of materials in the form of thin films that can exhibit strong nonlinear optical activity. Finally, the article discusses the present perspectives for the field and outlines some research directions that must be pursued for these materials to achieve their full range of potential applications.
Inorganic Nanocrystals: Patterning and Assembling
Authors: Curri Maria Lucia , Comparelli Roberto , Striccoli Marinella , Depalo Nicoletta , Fanizza Elisabetta 
Published: March 2009

AbstractRecently, increasing interest has been devoted to the study of the size‐dependent properties of inorganic nanocrystals and nanoparticles, in order to investigate and exploit their original potential. The ability to access nanoparticle properties for device fabrication is based on their organization in morphologically controlled assembly and/or ordered arrays, with suitable patterning, in order to bridge the gap between nanoscopic and mesoscopic scale.Assembly procedures allow the formation of original ordered state of matter and the fabrication of 2‐/3‐D patterned micro‐ and nanostructure, representing a promising route for producing functional materials and for processing and integrating the nanoparticles in macroscopic systems to fully develop their unprecedented functionality for materials and devices for biomedical, electronic, catalytic, and separation process technologies. Top‐down technological methods and techniques, conventional and emerging, have been cleverly and ingenuously combined and matched with dedicated bottom‐up approaches, paying attention to the peculiarity of the nanoparticle size regime. In most approaches, a precise control on the size and shape of the nanoparticles is crucial for driving the assembling and the extent to which the building blocks can be engineered, designed, and fabricated with desired features, including encoded instructions for assembling, has been greatly progressing in the last years. This article focuses on the potential of exploitation of inorganic nanocrystals and nanoparticles for assembling. An overview of the inorganic nanocrystal functions in the different and complementary strategies is outlined, highlighting the novelty and originality of the specific results and placing them in the scenario of the emerging material science, toward the envisioned creation of materials by design.
Semiconductor Nanocrystals: Doped Compositions
Authors: Vela Javier , Hollingsworth Jennifer A. 
Published: March 2009

Abstract
We review the state of the art in the field of semiconductor nanocrystal (SC NC) doping, with emphasis on cationic doping for modified optical and magnetic properties. Doping has the potential to greatly expand the already vast technological promise of SC NCs by allowing for the introduction of dopant‐specific or dopant‐modified properties. In the last several years, tremendous progress has been made with respect to both the understanding and implementation of SC NC–doping strategies. Here, we review the prevailing theoretical models (the “dopant extrusion model” and the “sticky surface model”) underpinning the current understanding of the process of dopant ion incorporation during NC growth. Further, we review the general synthetic approaches that have been developed in the context of this understanding, as well as many specific examples of SC NC–dopant systems, revealing both the successes and those that have fallen short in either achieving doping or fully demonstrating that doping was achieved. In support of this aim, we also provide a summary of the characterization methods (spectroscopic, structural, and chemical) that are critical for critiquing the doped system. We have necessarily focused on cationic doping as anionic doping has yet to be realized in a similar fashion. Further, the topic of electronic doping is only briefly addressed. While examples are reasonably abundant with respect to transition metal and lanthanide doping for modified magnetic/optical and optical properties respectively, permanent electronic doping of SC NCs has yet to be demonstrated. Finally, we identify (in addition to anionic and electronic doping) the topic areas that remain to be explored in this field of SC NC doping.
Molecular and Supramolecular Arrays of the [
Re
6
(μ
3
‐
Se
)
8
]
2+
Core‐Containing Clusters
Authors: Zheng Zhiping 
Published: March 2009

Abstract

Transition metal clusters are a unique class of chemical substances. Not only do they have well‐defined molecular structures, they also exhibit interesting and potentially useful properties that are inherent to metal–metal bonded species. In this contribution, our efforts in developing synthetic methodologies necessary to bring a cluster system out of the limited sphere of fundamental cluster chemistry and into general synthetic applicability are summarized. Specifically, we have explored the uses of site‐differentiated cluster complexes of the [Re
6
(μ
3
‐Se)
8
]
2+
core as stereospecific building blocks for supramolecular construction. A great variety of cluster‐supported molecular and supramolecular architectures have been realized. These include Tinkertoy‐like molecular cluster arrays featuring cluster units bridged by multitopic ligands and supramolecular assemblies of clusters engineered via hydrogen bonding and metal–ligand coordination. Some of these nanoscopic cluster‐containing systems display rather interesting electronic and spectroscopic properties and, therefore, hold great potential in developing molecule‐based electronic and optical materials. The work therefore marks the beginning of what promises to be an exciting new chapter in cluster chemistry.
Functional Supramolecular Hybrid Materials
Authors: Rurack Knut , Martínez‐Máñez Ramón 
Published: March 2009

AbstractThe combination of suitable nanoscopic inorganic supports with supramolecular concepts and bioconjugation strategies opens up exciting perspectives for the development of bioinorganic and organic–inorganic hybrid materials with improved functionalities. Many of the examples from the period 2004 to mid‐2007 reviewed here bridge the gap between molecules, materials sciences, biochemistry, and nanotechnology. The synergistic use of these approaches has led to the advancement of various functions such as enhanced recognition, amplified signaling, the controlled assembly and disassembly of aggregates and 3‐D architectures. Many of the implemented active functions can be carried out in a reversible and directed fashion on purpose by triggering with an external stimulus. These ideas bring tunability to properties of inorganic solids and new perspectives of application to biochemical and supramolecular concepts. Classic inorganic chemistries such as metal or semiconductor nanoparticles, silica or carbon materials, and coordination chemistry are thus elevated to another level of sophistication and contribute significantly to frontier research areas in directed transport and delivery, nanoelectronics and mechanics, chip technology, smart materials, memory devices, and bioanalytics.
Gold Nanoparticles as Chemical Catalysts
Authors: Ma Zhen , Overbury Steven H. , Dai Sheng 
Published: March 2009

Abstract

Gold, often known as being
chemically inert
, has rich inorganic and organic chemistry. In particular, gold nanoparticles, either protected by organic ligands or supported on solid surfaces, have attracted wide attention for their applications in catalysis, electronics, nonlinear optics, and biology. In this article, we summarize some recent advances in the synthesis of supported gold catalysts from the perspective of inorganic materials chemistry. These advances include new methods used to load gold, to prepare functionalized supports, and to postdecorate supported gold catalysts. More recent advances in the use of nanoparticle supports and other ordered nanostructures in making supported gold catalysts are also highlighted, and a critical analysis of the status of the field is presented. From this review, it is hoped that the reader will get an impression that inorganic materials chemistry can contribute to the synthesis of novel gold catalysts with good catalytic performance.
Semiconductor/Ceramic Nanocomposites: Synthesis, Characterization, and Properties
Authors: Moore Joshua T. 
Published: March 2009

Abstract
A survey of the preparation of semiconductor nanocrystal‐ceramic nanocomposite materials and related nanostructured materials is provided. Nanocomposite materials described here contain elemental semiconductors (Si and Ge), II–VI and IV–VI semiconductors (ZnE, CdE, and PbE where E = S, Se, Te), and III–V semiconductors (GaE, AlE, and InE where E = N, P, As) embedded in various ceramic matrices. Semiconductor nanocrystals and nanoparticles were prepared using a variety of physical, chemical, and electrochemical synthesis strategies. Sol‐gel processing, and single‐ or multiple‐source precursors were used to prepare semiconductor nanoparticles with diameters as small as 2–4 nm or as large as 50–200 nm. Formation of the semiconductor nanophase was carried out by reduction of mixed‐metal oxides, pyrolysis of well‐characterized precursor molecules or in situ generated precursor complexes, chemical vapor deposition (CVD), and electrochemical reduction.
Monodisperse Magnetic Nanoparticles: Chemical Synthesis and Surface Modification
Authors: Xie Jin , Sun Shouheng 
Published: March 2009

Abstract
Magnetic nanoparticles, due to their prospective applications in data storage, drug delivery, hyperthermia, and magnetic resonance imaging, have attracted considerable attention in the past decade. From aqueous‐phase condensation to organic‐phase thermal decomposition, the synthesis of magnetic nanoparticles has been greatly improved. Nowadays, one can readily synthesize monodisperse magnetic nanoparticles with controlled sizes, shapes, and magnetic properties. In this article, we first briefly describe the general synthesis of monodisperse nanoparticles, and then focus on the synthesis of magnetic nanoparticles via thermal decomposition of metal precursors. The nanoparticles are grouped into ferrite, metallic, alloy, and multicomponent categories, and the mechanism for the formation of nanoparticles with critical parameters in determining size, shape, and multifunctionality is discussed. We further summarize the chemistry used for nanoparticle surface functionalization and briefly discuss the potential applications of these magnetic nanoparticles in biomedicine.
Endohedral Fullerenes
Authors: Yang Shangfeng , Dunsch Lothar 
Published: March 2009

AbstractThe recent state in endohedral fullerenes is reviewed in terms of both sides of the fullerene: the new carbon cages including non‐IPR (IPR, isolated pentagon rule) structures as well as new species encaged in the inner fullerene void. A general principle is valid nowadays and used in endohedral fullerene research: the stabilizing ability of the encaged structure for the fullerene cage architecture and that of the fullerene cage for the encaged species. Thus, the cage size ranges from C66, the first non‐IPR fullerene cage, to C100while the encaged species are extended up to five atomic clusters as for Sc3C2. The world of endohedral fullerenes was significantly enlarged within the past seven years by the cluster fullerenes containing structures like the M3N nitrides. This review is focused on the new development of this amazing world of carbon nanostructures since 1999, including new structures, properties, and potential applications of endohedral fullerenes as well as prospects.
Inorganic Nanomaterials Synthesis Using Alkalide Reduction
Authors: Wagner Michael J. 
Published: March 2009

AbstractChemical (solution) methods of nanomaterial synthesis offer the advantages of simplicity, stoichiometric control, ease of scale‐up, and the possibilities of size control and narrow size distributions. Of the many solution methods of making nanoparticles, the reduction of metal salts by alkalides or electrides, generally referred to asalkalide reduction, is particularly promising due to its ability to protect highly oxyphilic elements and its use of the most power reductants possible in any given solvent. This makes it general across the periodic table including the early transition metals and rare earth elements. In fact, to date, it is the only solution method shown to be capable of synthesizing lanthanide metal nanoparticles. Binary and higher order phase nanomaterials are also possible by the simultaneous alkalide reduction of multiple elements. Nanoscale oxides and nitrides can be formed by reacting nanomaterials made by alkalide reduction with the appropriate gas. Spheroidal nanoparticles as small as ∼1 nm in diameter can be synthesized by this method as can rods up to ∼1 µm in length. The current practice and capabilities of highly versatile synthetic routes to nanomaterials are outlined in this article.
Biomimetic Chemistry of Hybrid Materials
Authors: Rurack Knut , Martínez‐Máñez Ramón 
Published: March 2009

AbstractThe article discusses representative examples published in the field of functional biomimetic chemistry of hybrid materials between 2004 and mid‐2007. First, we focus on the modification of morphological aspects of (bio)organic–inorganic hybrid materials to create sophisticated gating and switching mechanisms. The architecture of the systems is presented and the elements of control by external stimuli that have been established in recent years, such as optical, electrochemical, chemical, thermal, or magnetic means, are described. Various functions ranging from (site‐specific) delivery to indication at the nanometric level are reported. Next we develop the idea of utilizing hybrid frameworks for biomimetic signaling inspired by the way nature has created binding pockets and the concept of induced‐fit. Such a merging of inorganic scaffolds with supramolecular concepts results in enhanced molecular recognition and signaling. Finally selected recent advances in the field of hybrid biomimetic motors both of linear and rotary types are presented. The contribution shows how novel biomimetic functions can arise from synergisms between specifically designed hybrid materials and the implementation of supramolecular and/or bioorganic concepts.
Electrophilic Amination of Carbanions, Enolates, and Their Surrogates
Authors: Ciganek Engelbert 
Published: March 2009

AbstractThis chapter deals with the formation of carbon‐nitrogen bonds by reaction of carbon nucleophiles with electrophilic aminating reagents. The former encompass aliphatic and aromatic carbanions, enolates and their surrogates such as enamines, enol esters, and enol ethers, as well as carbanions stabilized by cyano or sulfone groups or by phosphorus. A section entitled Reagents and Mechanisms lists the many aminating reagents available and discusses the mechanisms by which the more important ones react. Among the electrophiles discussed are halo amines, various hydroxylamine derivatives, oxaziridines, imines, oximes, diazonium salts, diazo compounds, azo compounds, and azides. The section on Scope and Limitations is organized by carbon nucleophiles and attempts to suggest the best reagents for each class. A number of electrophilic aminating reagents that have been omitted from the scope of this chapter are briefly discussed, with references to reviews, in the section on Comparison with Other Methods. Tables listing references to the preparation of the various aminating reagents are found in the section on Experimental Conditions. References to the conversion of non‐amine products into amines are also provided there. The literature is covered to the middle of 2007.