nanoscale materials in chemistry, 2001, p.300

[...]... by placing nanocrystalline tin (7±10 nm) within an amorphous glass-forming matrix yielded nanocrystalline islands of tin enclosed by an amorphous oxide network Electrical conductivity can be maintained within such an electrode The advantage of such a nanostructural material is that the rather open structure of the glass helps to accommodate strain associated with the volume expansion during insertion... characteristic for all heavier main group elements and especially for all transition elements: they form metals The formation of a metallic state can best be illustrated by considering the interaction of, for instance, 2, 6, 10, etc and ®nally of an in nite number of lithium atoms having only a single electron in the 2s orbital Using the molecular orbital Nanoscale Materials in Chemistry, Edited by Kenneth... tougher coatings, replacements for body parts, ¯ameretardant plastics, replacements for metals, and more can be imagined.3 Self-cleaning and Unusual Coloring in Paints It has been demonstrated that when paints are doped with light-absorbing nanoparticles, such as TiO2, the paints are selfcleaning.3 The mechanism by which this happens is related to photooxidation of contaminants by TiO2 in water discussed... been invaluable in establishing the new ®eld of exciting scienti®c endeavor: nanostructured materials These and other synthetic advances will be described in much more detail in the following chapters 1.4 CLASSIFICATIONS OF NANOMATERIALS If we consider that the periodic table of the elements is ``a puzzle that has been given to us by God''43 that holds a huge treasure chest of new solid materials, think... Hearings, Summer, 1999 3 M C Roco, R S Williams, P Alivisatos (editors), Interagency Working Group in Nanoscience Engineering and Technology (IWGN) Workshop Report: Nanotechnology Research Directions; Vision for Nanotechnology R and D in the Next Decade, Published by Int Tech Research Institutes, WTEC Division, Loyola College, 1999, pp xxv, 58, 118, 67, xxvii, 70, 7, 102, 103 4 C A Merkin, R L Lestinger,... particle in a solid organic polymer, slicing very thin sections, and passing the electron beam through the section Scanning Probe Microscopy (SPM; also called Scanning Tunneling Microscopy, STM) and Related Atomic Force Microscopy (AFM)36 Discovery of the SPM technique took place in the 1980s It involves dragging a very sharp needlelike probe across a sample very close to the sample surface For conducting... were initially concerned with metal nanoparticles, led to the realization that essentially all solid materials in nanoscale would be of interest Thus, synthetic routes to metal oxides, sul®des, and other binuclear materials were developed or improved (sol-gels, aerogels, aerosol spray pyrolysis, inverse micelle methods, reactive evaporation of metals, zintyl salts, and others) All of these pioneering... important as vacuum seals, viscous dampers, and contamination exclusion seals With improvements, other applications may become important, such as their use as cooling ¯uids, nanoscale bearings, magnetically controlled heat conductors, and magnetic acids in separation of ores in mining and scrap metal separation.3,27 Better Batteries Nanostructural materials in lithium ion batteries have proven to be very... thin ®lms; one dimension 3 thin wire Nanophase material The same as nanostructured material Quantum dot A particle that exhibits a size quantization effect in at least one dimension After this introduction, it is appropriate that the topic of nanostructured materials in chemistry is considered in more detail, which is taken up in the following chapters First, important chapters on the three major materials metals,... tunneling mode There continue to be developments in this area, and magnetic mapping is also possible Powder X-Ray Diffraction (XRD) Although XRD has been useful for crystalline powders for several decades, modern improvements in electronics, computers, and X-ray sources have allowed it to become an indispensable tool for identifying nanocrystalline phases as well as crystal size and crystal strain Other . such nanoscale particles, including magnetic properties, optical properties, melting points, speci®c heats, and surface reactivity. Furthermore, when such ultra®ne particles are consolidated into. elevated portion of the sample, the probe moves up and over, and by rastering over an area of the sample, a surface map can be produced. With proper sample preparation and using a high-quality instrument. yield a new set of properties, dependent on size. Optical properties, magnetic properties, melting points, speci®c heats, and crystal morphologies can all be in uenced because nanomaterials serve