TABLE OF CONTENTS Nanotechnology offers an extremely broad range of potential applications from electronics, optical communications and biological systems to new materials. Many possible applications have been explored and many devices and systems have been studied. More potential applications and new devices are being proposed in literature. It is obviously impossible to summarize all the devices and applications that have been studied and it is impossible to predict new applications and devices. This chapter will simply provide some examples to illustrate the possibilities of nanostructures and nanomaterials in device fabrication and applications. It is interesting to note that the applications of nanotechnology in different fields have distinctly different demands, and thus face very different challenges, which require different approaches. For example, for applications in medicine, or in nanomedicine, the major challenge is "miniaturization": new instruments to analyze tissues literally down to the molecular level, sensors smaller than a cell allowing to look at ongoing functions, and small machines that literally circulate within a human body pursuing pathogens and neutralizing chemical toxins. [1]
Applications of nanostructures and nanomaterials are based on (i) the peculiar physical properties of nanosized materials, e.g. gold nanoparticles used as inorganic dye to introduce colors into glass and as low temperature catalyst, (ii) the huge surface area, such as mesoporous titania for photoelectrochemical cells, and nanoparticles for various sensors, and (iii) the small size that offers extra possibilities for manipulation and room for accommodating multiple functionalities. For many applications, new materials and new properties are introduced. For example,...
