Metal-based nanostructures, for their peculiar properties, have been extensively used in applications such as catalysis, electronics, photography, and information storage, among others. New applications for metals in areas such as photonics, sensing, imaging, and medicine have also being developed. Significantly, most of these applications require the use of metals in the form of nanostructures with specific controlled properties. The properties of a nano-scale metals are determined by a set of physical parameters that include the size, shape, composition, and structure. In recent years, many research fields have focused on the synthesis of nano-scale size metallic materials with complex shape and composition in order to optimize the optical and electrical response of devices containing metallic nanostructures. The present paper aims to overview the most recent results, in terms of fabrication methodologies, characterization of the physico-chemical properties and applications, of complex-morphology metal-based nanostructures. The paper aims to strongly focus on the correlation between the complex-morphology and the structures properties showing how, often, the morphological complexity (and its nanoscale control) can give access to a wide range of innovative properties exploitable for innovative functional devices production. We begin with an overview of the basic concepts on the correlation between structural and optical parameters of nano-scale metallic materials with complex shape and composition, and the possible solutions offered by nanotechnology in a large range of applications (catalysis, electronics, photonics, sensing). The aim is to assess the state of the art, and then show the innovative contributions that can be proposed in this research field. Then, we report on innovative, versatile and low-cost synthesis techniques, suitable to provide a good control on the size, surface density, composition and geometry of the metallic nanostructures. The main purpose of this study is the fabrication of functional nanoscale-size materials, whose properties can be tailored (in a wide range) simply by controlling the structural characteristics. The modulation of the structural parameters is required to tune the plasmonic properties of the nanostructures for applications such as biosensors, opto-electronic or photovoltaic devices and SERS substrates. The structural characterization of the obtained nano-scale materials is employed in order to define how the synthesis parameters affect the structural characteristics of the resulting metallic nanostructures. Then, macroscopic measurements are used to probe their electrical and optical properties. Phenomenological growth models are drafted to explain the processes involved in the growth and evolution of such composite systems. After the synthesis and characterization of the metallic nanostructures, we study the effects of the incorporation of the complex morphologies on the optical and electrical responses of each specific device.
|Titolo:||Complex-Morphology Metal-Based Nanostructures: Fabrication, Characterization, and Applications|
|Autori interni:||GRIMALDI, Maria Grazia|
|Data di pubblicazione:||2016|
|Appare nelle tipologie:||1.1 Articolo in rivista|