COLL 354 |
| Photochemical reactions on oxide surfaces typically occur in the presence of water. In the case of organic photooxidation, the influence of water has been categorized as 'promoting' when OH radical production is considered key and/or 'inhibiting' when the stronger adsorption strength of water results in displacement of weakly bound organics from the oxide surface. An example of the latter effect is found in the photodecomposition of acetone on rutile TiO2(110). A third effect, shown for the photodecomposition of trimethyl acetate, is presented in this talk in which the development of a reaction front between hydrophilic and hydrophobic domains significantly shifts the rate and pathway of a photooxidation reaction. Based on this example, the impact of hydrophilic-hydrophobic domains on rates and selectivities should be present in other heterogeneous photochemical reactions were competition for surface sites exists between water, organics and molecular oxygen. Work supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences. |
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The Physical Chemistry of Environmental Interfaces
8:30 AM-12:40 PM, Wednesday, April 9, 2008 Morial Convention Center -- Rm. 225, Oral
Division of Colloid & Surface Chemistry |