A spectroscopic study for the application of a PEDOT-type material as buffer layer in electronic devices

The properties of polymer blend prepared by the polymerization of 3,4-(ethylenedioxy)thiophene in the presence of iron(III) toluensulfonate (PEDOT:PTSA) as well as the interface properties of the NiPc/PEDOT:PTSA system were investigated by X-ray and UV photoemission spectroscopies. The results are compared with those studied previously for NiPc/PEDOT:PSS (poly[3,4-(ethylenedioxy)thiophene]-sulfonated polystyrene) and NiPc/ITO interfaces. The non-reactive NiPc/Au interface was used as a reference for the determination of the Fermi level position in NiPc. Different properties observed for the NiPc/PEDOT:PTSA and NiPc/PEDOT:PSS interfaces are discussed in the frame of different chemical structures of both polymers.