| This work explores the effect of the shape of metal nanoscale building blocks on the structural, optical, and plasmonic properties of their assemblies, as well as on the catalytic performance and hydrogen interactions of individual nanoparticles with specific shapes. In Chapter 3, I describe the linear self-assembly of bifunctional metal nanoparticles in the presence of monofunctional nanoscale chain stoppers. Chain stoppers with controlled reactivity were synthesized allowing control over the morphology of the self-assembled structures. Analysis of the degree of polymerization of linear nanostructures provided information about self-assembly kinetics, side reactions, and the distribution of species in the reaction. This work facilitated testing of theoretical models developed for molecular polymerization and fabrication of linear nanoparticle assemblies with controllable properties. In Chapter 4, I developed linear solution-based self-assembly of cubic metal nanoparticles, examined the morphology of the nanocube chains and their optical characteristics. In comparison with chains of nanospheres with similar dimensions, compositions, and surface chemistry, predominant face-to-face assembly of nanocubes leads to a larger volume of plasmonic hot spots, uniform electromagnetic field enhancement in the gaps between nanocubes, and a new coupling mode for nanocube chains, associated with Fabry-Perot structure. In Chapter 5, I investigated plasmon-mediated enhancement of the catalysis by palladium-based nanoparticles with different shapes and composition, bearing surface plasmon resonance in visible range. The photocatalytic activity of palladium-based nanoparticles depended more on their shape than internal structure. These findings pave the way for the design of palladium nanocatalysts with enhanced performance acting under visible light illumination. In Chapter 6, I developed a facile scaled-up synthesis of monodisperse palladium nanoparticles with various shapes, stabilized with a mesoporous silica shell. Hydrogen-nanoparticle interactions were studied using temperature programmed desorption. These findings help elucidate the nature of hydrogen interactions with topologically different palladium nanoparticles. |
