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A physical chemistry experiment illustrating photochemistry, cyclic voltammetry, the properties of semiconductors, and surface chemistry is described. The experiment consists of constructing a liquid-junction photochemical cell, determining the cell parameters, then modifying the surface of the electrode to enhance the conversion efficiency of the cell. The students will learn some fundamental physical and chemical principles related to light and electricity interconversion as well as the properties of semiconductors. The experiment can also be developed into an undergraduate research or independent study project.

The adsorption and thermal decomposition of a perfluorinated ether and an alkyl ether have been studied on the TiO2 surface using Fourier transform infrared spectroscopy. It has been found that the fully fluorinated ether, (C2F5)2O, physisorbed onto the TiO2 surface. As the surface was heated to 500 K, it was found that the (C2F5)2O thermally decomposed to a surface fluoroacetate species at temperatures greater than 200 K. The more acidic surface hydroxyl groups are permanently perturbed by the oxidation reaction, indicating interaction of the ether with the surface hydroxyl groups. The fully hydrogenated ether, (C2H5)2O, decomposed on the TiO2 surface to form a surface ethoxide at temperatures greater than 150 K. The more acidic surface hydroxyl groups are involved in this chemical reaction and do not recover by 500 K.