Catalyzing the Oxygen-Assisted Coupling of Methanol with Au and (Ag)Au Nanoparticles

Continuous growth in global energy demand necessitates the improvement of energy-saving technologies. Development of better catalysts offers a path to significant reductions in energy use by the chemical industrial sector, but design of highly active and selective catalytic materials is an ongoing challenge. Nanoparticles show promise in accelerating this development process because their synthetic flexibility allows for rational design of catalyst size, structure, and composition. This thesis demonstrates how this capacity to strategically design the characteristics of nanoparticles makes them an effective tool to experimentally verify calculated predictions about catalytic active sites. Chapter 1 describes the fundamental principles of nanoparticle growth that afford them their great synthetic flexibility and presents some important guiding concepts about heterogeneous catalysis. Chapter 2 outlines how the application of dilute (Ag)Au alloy concave cubes to experimentally verify a calculated prediction about active sites in (Ag)Au alloys led to an active, selective, robust catalytic material that is activated without the use of a typical ozone pretreatment for the oxygen-assisted coupling of methanol. Chapter 3 explores the unusual capacity of monometallic Au nanoparticle surfaces to activate molecular oxygen, potentially through a mechanism in which an active species left over from particle synthesis acts as a catalytic promoter. As a whole, the work presented in thesis represents an important addition towards the application of nanoparticles as catalytic materials and as research tools to better understand the fundamental ideas of catalysis.