tailieunhanh - Characterization of Nanophase Materials

Engineering of nanophase materials and devices is of vital interest in electronics, semiconductors and optics, catalysis, ceramics and magnetism. Research associated with nanoparticles has widely spread and diffused into every field of scientific research, forming a trend of nanocrystal engineered materials. | Characterization of Nanophase- Materials. Edited by Zhong Lin Wang Copyright 2000 Wiley-VCH Verlag GmbH ISBNs 3-527-29837-1 Hardcover 3-527-60009-4 Electronic Part I Technical Approaches Characterization of Nanophase- Materials. Edited by Zhong Lin Wang Copyright 2000 Wiley-VCH Verlag GmbH ISBNs 3-527-29837-1 Hardcover 3-527-60009-4 Electronic 1 Nanomaterials for Nanoscience and Nanotechnology Zhong Lin Wang Technology in the twenty first century requires the miniaturization of devices into nanometer sizes while their ultimate performance is dramatically enhanced. This raises many issues regarding to new materials for achieving specific functionality and selectivity. Nanophase and nanostructured materials a new branch of materials research are attracting a great deal of attention because of their potential applications in areas such as electronics 1 optics 2 catalysis 3 ceramics 4 magnetic data storage 5 6 and nanocomposites. The unique properties and the improved performances of nanomaterials are determined by their sizes surface structures and interparticle interactions. The role played by particle size is comparable in some cases to the particle chemical composition adding another flexible parameter for designing and controlling their behavior. To fully understand the impacts of nanomaterials in nanoscience and nanotechnology and answer the question of why nanomaterials is so special this chapter reviews some of the unique properties of nanomaterials aiming at elucidating their distinct characteristics. Why nanomaterials Nanomaterials are classified into nanostructured materials and nanophase nano-particle materials. The former refer to condensed bulk materials that are made of grains with grain sizes in the nanometer size range while the latter are usually the dispersive nanoparticles. The nanometer size here covers a wide range which can be as large as 100-200 nm. To distinguish nanomaterials from bulk it is vitally important to demonstrate the unique .