Engineering core-shell plasmonic nanoMOFs: synthetic methodologies and applications

Abstract

This thesis aims to develop synthetic methods for core-shell composite materials, where the core consists of gold plasmonic nanoparticles with various morphologies, and the shell is composed of hybrid materials known as metal-organic frameworks (MOFs). The plasmonic cores of these materials exhibit unique optical properties due to the presence of surface plasmons, which are generated by the nature of the metallic bond. This bond can be defined as a "sea of free electrons" that traverse the condensed lattice of metal cations. When these electrons are excited by light, they oscillate on the surface of the metal. At the nanoscale, the confinement of the electrons plays a key role in the excitation of these plasmons, allowing this oscillation to be tuned for excitation with visible or infrared light, depending on factors such as chemical composition, size, shape, the presence of stabilizing agents on the surface, or the surrounding dielectric environment. This oscillation presents an absorption maximum known as localized surface plasmon resonance (LSPR), which generates electric dipoles in specific regions of the nanoparticle that can be exploited in various applications.