Synthesis and characterization of silver Ag polyvinyl alcohol PVA nanocomposites and their applications in electronics and photonics

Abstract

Nanocomposite materials have created a new generation of materials that exhibit unique physical and chemical properties making them attractive for applications in various fields/applications of Science and Technology viz. Electronics, photonics, Optics, Catalysis, Sensors etc. The nanocomposite materials of plasmonic nanoparticles like Ag, Au etc. and polymer matrix like PVA are widely studied in recent years due to their unusual properties which considerably differ from their bulk counterpart. The present thesis is about the synthesis, characterizations and applications of Ag/PVA nanocomposites in Electronics and Photonics. The Localized Surface Plasmon Resonance (LSPR), Coulomb Blockade Effect, Superparamagnetism, Interfacial polarization etc. are some unique properties of these materials for which they are most useful materials for device applications. Thermal annealing process, a simple and fast synthesis process is used for generating Ag nanoparticles in PVA matrix. This process is free from using extra reducing and stabilizing agents as the matrix PVA itself performs both the functions. The effect of different fabricating parameters like annealing time and temperature, molecular weight ratio of Ag and PVA etc. on the particle size and shape are illustrated in this thesis. The optical and morphological characterizations and finer details of the particles in the samples are carried out through Ultra Violet-Visible (UV-VIS), Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) method. The size of Ag nanoparticles in PVA matrix is also estimated theoretically based on classical Mie Scattering theory. The fabricated Ag/PVA nanocomposites are applied as dielectric material in thin film capacitor considering the Coulomb Blockade Effect and Interfacial Polarization of Ag/PVA nanocomposites and their capacitive properties are compared with those of their bulk counterpart and the matrix alone. The effect of the degree of coating on the capacitive properties of the capacitor is also investigated. The...