title: Structure-function relationships in unsymmetrical zinc phthalocyanines for dye-sensitized solar cells.
abstract: A series of unsymmetrical zinc phthalocyanines bearing an anchoring carboxylic function linked to the phthalocyanine ring through different spacers were designed for dye-sensitised solar cells (DSSC). The modification of the spacer group allows not only a variable distance between the dye and the nanocrystalline TiO(2), but also a distinct orientation of the phthalocyanine on the semiconductor surface. The photovoltaic data show that the nature of the spacer group plays a significant role in the electron injection from the photo-excited dye into the nanocrystalline TiO(2) semiconductor, the recombination rates and the efficiency of the cells. The incident monochromatic photon-to-current conversion efficiency (IPCE) for phthalocyanines bearing an insulating spacer is as low as 9%, whereas for those with a conducting spacer an outstanding IPCE 80% was obtained.
authors.affiliation: Departamento de Química Orgánica, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid, Spain.
authors.forename: Juan-José
authors.initials: JJ
authors.lastname: Cid
authors.forename: Miguel
authors.initials: M
authors.lastname: García-Iglesias
authors.forename: Jun-Ho
authors.initials: JH
authors.lastname: Yum
authors.forename: Amparo
authors.initials: A
authors.lastname: Forneli
authors.forename: Josep
authors.initials: J
authors.lastname: Albero
authors.forename: Eugenia
authors.initials: E
authors.lastname: Martínez-Ferrero
authors.forename: Purificación
authors.initials: P
authors.lastname: Vázquez
authors.forename: Michael
authors.initials: M
authors.lastname: Grätzel
authors.forename: Mohammad K
authors.initials: MK
authors.lastname: Nazeeruddin
authors.forename: Emilio
authors.initials: E
authors.lastname: Palomares
authors.forename: Tomás
authors.initials: T
authors.lastname: Torres