Characteristics of the phosphorescence spectra of benzophenone adsorbed onTi-Al binary oxides

The excited states of benzophenone adsorbed on well-characterized Ti-Al bin ary oxides were investigated by means of conventional molecular spectroscop ic techniques such as UV and In absorption as well as photoluminescence spe ctra measurements. It was found that the photochemical and photophysical pr operties of benzophenone adsorbed on the oxide surfaces strongly depend on their surface properties, which are systematically changed by changing the composition of the oxides. Specifically, the phosphorescence spectra of ben zophenone adsorbed on the oxides have been found to be composed of the hydr ogen-bonded benzophenone species and the protonated benzophenone species.