Au nanoparticles supported on reducible metal oxide surfaces are known to be active catalysts for a number of reactions including CO oxidation and hydrogen production. The exact choice of a metal oxide support has been shown to have a marked impact on activity, suggesting that interactions between Au and the support play a key role in catalysis. For TiO2, a model substrate for Au catalysis, it ...

TiO2-supported catalysts have been widely used for a range of both liquid-phase and gas-phase hydrogenation reactions. However, little is known about the effect their different crystalline surfaces on activity during hydrodeoxygenation process. In this work, Au supported anatase TiO2, mainly exposing 101 or 001 facets, was investigated (HDO) guaiacol. At 300 °C, strong interaction between TiO2-...

Recent experiments on CO oxidation reaction using seven-atom Au clusters deposited on TiO2 surface correlate CO2 formation with oxygen associated with Au clusters. We perform first principles calculations using a seven-atom Au cluster supported on a reduced TiO2 surface to explore potential candidates for the form of reactive oxygen. These calculations suggest a thermodynamically favorable path...

Rhodamine B (RB) is a toxic dye used extensively in textile industry, which must be remediated before its drainage to environment. In the present study, supported gold nanoparticles on commercially available titania and zincite were successfully prepared and then their activity on the photodegradation of RB under UV A light irradiation were evaluated. The synthesized photocatalysts were charact...

Model catalysts of Au clusters supported on TiO2 thin films were prepared under ultra-high vacuum (UHV) conditions with average metal cluster sizes that varied from ∼2.5 to ∼6.0 nm. The reactivities of these Au/TiO2 catalysts were measured for CO oxidation at a total pressure of 40 Torr in a reactor contiguous to the surface analysis chamber. Catalyst structure and composition were monitored wi...

The chemoselective continuous gas phase (T = 573 K; P = 1 atm) hydrogenation of nitroarenes (p-chloronitrobenzene (p-CNB) and m-dinitrobenzene (m-DNB)) has been investigated over a series of oxide (Al2O3 and TiO2) supported Au and Ni-Au (1 : 10 mol ratio; 0.1-1 mol% Au) catalysts. Monometallic supported Au with mean particle size 3-9 nm promoted exclusive formation of p-chloroaniline (p-CAN) an...

Density functional theory is used to determine the reaction mechanisms of CO oxidation and the active oxygen species on a Au/TiO2 model catalyst. The model consists of a Au rod supported along the TiO2 [11̅0] direction of the TiO2(110) surface. An interfacial Au/Ti5c site at the interface boundary is identified to be particularly active toward O2 adsorption and dissociation. At this site, O2 dis...

As models for probing the interactions between TiO2 surfaces and the dye molecules employed in dye-sensitized solar cells, carboxylic acids are an important class of molecules. In this work, we present a scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED) study of three small carboxylic acids (formic, acetic, and benzoic) that were reacted with the TiO2(110) surface v...

We studied the competition between energy loss due to quenching and enhanced absorption arising from the near-field plasmonic effect of Au nanoparticles (NPs) on the performance of organic solar cells (OSCs), by fabricating inverted architecture OSCs with electron transport layers consisting of an Au NPs monolayer covered by a ZnO overlayer. The distance between Au NPs and a poly(3hexylthiophen...

The interaction of carbon monoxide and oxygen with gold particles supported on zinc oxide, alumina, and titania was investigated by microcalorimetry. Multiple processes were detected during CO adsorption, including adsorption of CO on the gold particles and support, oxidation of CO, and formation of carbonates. The rate of O2 adsorption was much slower than that of CO adsorption. The heats and ...