| AVS 56th International Symposium & Exhibition | |
| Electronic Materials and Processing | Tuesday Sessions |
| Session EM-TuP |
| Session: | Electronic Materials and Processing Poster Session |
| Presenter: | R. Schlaf, University of South Florida |
| Authors: | S. Gutmann, University of South Florida M. Wolak, University of South Florida M.M. Beerbom, University of South Florida R. Schlaf, University of South Florida |
| Correspondent: | Click to Email |
The electronic structure of the interfaces in dye-sensitized solar cell structures was investigated using x-ray and ultraviolet photoemission spectroscopy (XPS, UPS). Electrospray thin film deposition in high vacuum was used to build the interfaces of interest directly in vacuum without exposure to the ambient. Electrospray enables the fabrication of clean, essentially uncontaminated thin films of organic molecules and nanoparticles directly in vacuum.
The experiments focused on the investigation of the indium tin oxide (ITO)/nanocrystalline TiO2 interface, as well as the characterization of the TiO2/RuL2(NCS)2 [cis-bis(4,4’-dicarboxy-2,2’-bipyridine)–bis(isothio-cyanato)-ruthenium(II)] (“N3”, a prototypical dye used in many currently pursued device structures)-dye interface. Both TiO2 and N3 films were built up in several steps. After each step, characterization by XPS and UPS was performed. The resulting sequence of spectra allowed the determination of charge injection barriers and interface dipoles at the ITO/TiO2 and TiO2/N3 interfaces. A particular focus of the experiments was the investigation of the influence of different surface conditions of the ITO on the electron injection barriers between TiO2 and ITO.