X-ray photoelectron spectroscopy of fluorescein adsorbed on model solar-cell surfaces

We report on the X-ray photoelectron spectroscopy of fluorescein molecules adsorbed under UHV conditions on single crystal rutile TiO2(1 1 0) and Au/TiO2(1 1 0) surfaces. The molecule is thought to bond covalently to these model solar-cell surfaces primarily through the deprotonated carboxylic group, with an additional interaction arising between the triple ring structure of the molecule and the surface.