(582av) Gold Nanoparticle Clusters As Fenton Reaction Photocatalysts

The formation of inter-particle junctions (hotspots) increases the electron density and near-field intensity between assemblies of plasmonic nanoparticles in the presence of light. The influence of these hotspots on the rate of heterogeneous photocatalysis is not well understood. In this talk, we will discuss experiments designed to understand the influence of hotspots on heterogeneous photocatalysis. The degradation of methylene blue using gold nanoparticles in the presence of light will be studied as the basis system. These experiment use the Fenton reaction mechanism where hydroxyl radicals (OH·) will be generated for the oxidation of organic molecules. Previous work by Navalon et.al demonstrated that gold nanoparticles enhanced the degradation of an organic compound using the Fenton reaction mechanism in the presence of a monochromatic light of 532 nm and using broad-spectrum solar light¹. In the previous study, gold nanoparticles enhanced the formation of solvated electrons that aided in the formation of hydroxyl radical and increased the oxidation rate of the basis compound, phenol¹. In this presentation, we discuss experimental results that were designed to study to what extent clusters of gold nanoparticles demonstrate an enhanced photocatalytic effect compared to gold monomers based on the rate of degradation of methylene blue. Nanoparticles with enhanced hotspots due to electromagnetic radiation and directed self-assemble have a number of applications, including but not limited to wastewater treatment and commodity chemical catalysis.

Reference:

1. Navalon, S.; Miguel, M.; Martin, R.; Alvaro, M.; Garcia, H.; J. Am. Chem. Soc. 2011, 133, 2218-2226.