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Abstract
Nanostructures have been explored considerably in recent times to ascertain the unique properties they exhibit in the nanoscale regime as opposed to their bulk counterparts. Their characteristic high surface-to-volume ratio coupled with confinement effects contribute to altering physical properties and phenomena as a function of diminishing material dimensions. Core/ shell nanoparticles are fast emerging as a preferred class of nanostructures because of the additional flexibility they offer in providing tailored properties for specific applications.Electronic conductive properties in composite structures and the parameters responsible for conduction have captivated the interest of researchers for years. Apart from representing a challenging field in a purely academic sense, the method of characterization based on charge transport is seen as a useful tool for efficiently extricating novel behavior exhibited by nanostructures for use in modern technologies. In this dissertation, the charge transport characteristics of three-dimensional disordered arrays of two different core/ shell nanostructure samples have been analyzed. A copper core/ copper oxide shell sample representing metal core/ metal oxide shell architecture, and a gold core/ silicon dioxide shell sample with the metal core/ insulator shell type of architecture have been used. Careful experimentation on charge transport through the samples reveal non-ohmic conduction trends in both the cases. Furthermore, it is also found that while the Cu/CuxO sample displays a sharp increase in conductivity after a certain threshold temperature, the Au/SiO2 sample exhibits a gradual increase in conductivity without any abrupt transition. Various theoretical models have been analyzed to establish the nature of charge transfer mechanisms that predominate in the samples over the wide range of experimental conditions they are exposed to, while considering parameters like the type of core and shell materials considered, particle dimensions, and their structure.