An Insight into Properties and Characterization of Nanostructures

Nanostructures are one of the pivotal structures in nanotechnology that are widely used in various fields like photonics, quantum computation and energy applications. Nanostructures are structures that have size in the range of 1–100 nm. The classification of nanostructures is discussed briefly in the view of confinement of electrons. Based on the quantum confinement of electrons, nanostructures are divided into three categories such as 1D, 2D and 3D nanostructures. Nanostructures possess novel properties such as physical (electronic, optical and thermal), transport and mechanical properties (hardness and fatigue) that are dependent on their sizes. The properties of nanostructures are entirely different from their bulk counterparts because of having large surface-to-volume ratio. It is always difficult to fabricate functional nanostructured surfaces, but the most important activity is the ability to characterize their features, shapes, morphology, size, etc., and then to correlate their physical properties to these characteristics. In nanomaterials, the physical properties include size, morphologies and surface area, and the chemical properties include composition, surface, electrochemistry and oxidation states. This chapter deals with the properties of nanostructures and various techniques required for their characterizations. The main objective of characterization of nanostructures is to achieve a nanoscale comprehension of the physical and chemical aspects of nanostructures. For this purpose, different characterization techniques such as Raman and fluorescence spectroscopy, TEM, SEM, STEM, STM, AFM, molecular modeling, X-ray diffraction, X-ray photoelectron spectroscopy, wide and small-angle X-ray scattering, X-ray tomography and nuclear magnetic resonance are described in detail.