Study of anisotropic interfacial electron transfer across a semiconductor/solution interface by time-resolved EPR spectroscopy

(Figure Presented) Xanthene dyes absorbed onto colloidal TiO2 exhibit spin-polarized EPR spectra when excited with pulses of visible light at low temperatures (see schematic representation). Analysis of the spectra enables the range of distances between the electron and the dye radical cation as well as their relative orientations to be determined. Furthermore, an orientational selectivity in electron transfer across the semiconductor nanoparticle is observed. © 2005 Wiley-VCH Verlag GmbH & Co. KGaA.