TABLE OF CONTENTS Nanophase materials generally refer to material systems consisting of interconnected nanodomains or other nanocomponents. These nanodomains, by definition, contain only a small number of atoms tightly bound together by an attractive potential; their sizes are usually in the range of 1 nm to 100 nm. Nanophase materials often exhibit novel chemical, electrical, optical, mechanical, or magnetic properties different from their bulk materials and the individual atomic constituents.
A unique feature of nanodomains is that a large fraction of the atoms are located on the surfaces of the domains; nanodomains have a high surface-to-bulk atom ratio. When these nanodomains are joined to form bulk nanophase materials, a large number of interfaces or grain boundaries are created. Atoms located at interfaces or grain boundaries are flexible and dynamic: they interact with and conform to the surrounding environment. Relaxation and reconstruction can relocate interfacial atoms from their bulk-like positions; the nature and the number of atoms surrounding an interfacial atom can be very different from those of atoms located within the nanograins. The interfacial regions or grain boundaries introduce new electronic or crystal structures. Thus, a nanophase material can be treated as a nanocomposite consisting of at least two phases: one phase is related to the atoms located within the nanograins and another phase is related to the atoms located at grain boundaries or interfaces.
Various nanophase materials and their applications have been discussed in the previous chapters. In this chapter, we will discuss electrochromic properties...
