Organic photoconductors with C60 for xerography Original Research Article

Our aim is to improve the charge-generation efficiency of organic-photoreceptor materials used in xerography and for laser printers by mixing the material with buckminsterfullerene C60. The improvement is based on an electron transfer from the excited excitonic state of the photoreceptor molecule to the C60 thus reducing the recombination probability. Typical materials studied are various metal-phthalocyanines (M-Pc, with M=TiO, VO, Ni, Fe, Cu) and metal-free H2-Pc. Using techniques like X-ray absorption near edge spectroscopy (XANES) and photoelectron spectroscopy with ultraviolet radiation (UPS) we demonstrate that the electron transfer is energetically possible and no ground state electron transfer occurs. The observation of fluorescence quenching upon doping with C60 validates the electron transfer-model.