title: Sensitization of nanocrystalline TiO2 with black absorbers based on Os and Ru polypyridine complexes.
abstract: New metal complexes of the type [M(H3tcterpy)LY]+ (where M = Os(II) or Ru(II), L = substituted or unsubstituted bipyridine or pyridylquinoline, and Y = Cl-, I-, or SCN-) have been designed, synthesized, and characterized in view of their application for dye-sensitized solar cells (DSSCs). The Os dyes show a very broad absorption, and correspondingly, the DSSCs show an unprecedented spectral response in the NIR, with an onset at 1100 nm, reaching values of about 50% at 900 nm. The integrated photocurrent of some of such Os dyes is similar to that of the well-known [Ru(Htcterpy)(NCS)3](TBA) and superior to that of the [Ru(Hdcbpy)2(NCS)2](TBA)2 sensitizer. The Ru dyes show absorption and DSSC spectral response between those of the red and black dyes. Their advantage is their potential superior stability due to the reversible oxidative electrochemistry.
authors.affiliation: Dipartimento di Chimica and Istituto per la Sintesi Organica e la Fotoreattività (ISOF-CNR), Università di Ferrara, 44100 Ferrara, Italy.
authors.forename: Silvano
authors.initials: S
authors.lastname: Altobello
authors.forename: Roberto
authors.initials: R
authors.lastname: Argazzi
authors.forename: Stefano
authors.initials: S
authors.lastname: Caramori
authors.forename: Cristiano
authors.initials: C
authors.lastname: Contado
authors.forename: Simone
authors.initials: S
authors.lastname: Da Fré
authors.forename: Patrizia
authors.initials: P
authors.lastname: Rubino
authors.forename: Christophe
authors.initials: C
authors.lastname: Choné
authors.forename: Gerardo
authors.initials: G
authors.lastname: Larramona
authors.forename: Carlo Alberto
authors.initials: CA
authors.lastname: Bignozzi