| The effects of 397 nm laser irradiation of spin-coated films of the photoacid generator, p-nitrobenzyl 9,10-dimethoxyanthracene-2-sulfonate (NBAS), have been studied by X-ray photoelectron and Fourier transform infrared spectroscopies (XPS and FTIR). XPS has also been used to study the adsorption of poly(diallyldimethylammonium chloride), a cationic polyelectrolyte, on NBAS films as a function of pH.; In the second part of this thesis the chemical compositions of five ruthenium dyes were studied by X-ray photoelectron spectroscopy (XPS). The energies of the highest occupied molecular orbitals (HOMO) and the lowest unoccupied molecular orbitals (LUMO) of dyes and anatase TiO2 were obtained by correlating ultraviolet photoelectron spectroscopy (UPS) and UV-vis absorbance spectroscopy. Such measurements permit assessment of the energy level alignment of dyes and the TiO2 semiconductor. Energy level matching of the excited vibrational states of dyes and the conduction band edge of TiO 2 can promote electron injection from the dye to TiO2, an important factor related to the efficiency of dye-sensitized photovoltaic devices. (Abstract shortened by UMI.)... |
