title: TiO2 nanocrystals shell layer on highly conducting indium tin oxide nanowire for photovoltaic devices.
abstract: We demonstrated a highly efficient conducting indium tin oxide (ITO) core-TiO2 nanocrystals shell nanowire array for a photoelectrode in dye-sensitized solar cells with regard to light harvest and charge collection. The TiO2 shell layer, consisting of anatase nanocrystals of ~2 nm, were successfully formed on a single crystalline ITO nanowire prepared via a vapor transport method using repetitive TiCl4 aqueous solution treatments at 50 °C. We found that the nanocrystal size and number of Cl(-) ions remaining on the formed shell layer critically influence the dye loading properties. Moreover, these factors can be controlled by means of a post-annealing process. We also found that the dye loading and the back electron transport from the conductive ITO nanowire to the electrolyte mainly determine the final cell performance. The proposed double-shell layer structure consisting of dense and porous layers showed significantly improved cell performance.
authors.affiliation: WCU Hybrid Materials Program, Department of Materials Science & Engineering, Seoul National University, Seoul 151-742, Korea.
authors.forename: Hyun Soo
authors.initials: HS
authors.lastname: Han
authors.forename: Ju Seong
authors.initials: JS
authors.lastname: Kim
authors.forename: Dong Hoe
authors.initials: DH
authors.lastname: Kim
authors.forename: Gil Sang
authors.initials: GS
authors.lastname: Han
authors.forename: Hyun Suk
authors.initials: HS
authors.lastname: Jung
authors.forename: Jun Hong
authors.initials: JH
authors.lastname: Noh
authors.forename: Kug Sun
authors.initials: KS
authors.lastname: Hong