Maria-Eleni Ragoussi

Carboxyethynyl Anchoring Ligands: A Means to Improving the Efficiency of Phthalocyanine-Sensitized Solar Cells†

Keywords: conjugation ; electron transfer ; solar cells ; synthetic methods ; zinc ; Conversion Efficiency ; Porphyrin Sensitizers ; Tio2 ; Dyes Reference EPFL-ARTICLE-177266doi:10.1002/anie.201108963View record in Web of Science Record created on 2012-05-18, modified on 2016-08-09

Sterically Hindered Phthalocyanines for Dye‐Sensitized Solar Cells: Influence of the Distance between the Aromatic Core and the Anchoring Group

A new phthalocyanine (Pc) bearing bulky peripheral substituents and a carboxylic anchoring group directly attached to the macrocycle has been prepared and used as a sensitizer in DSSCs, reaching 5.57% power conversion efficiency. In addition, an enhanced performance for the TT40 dye, previously reported by us, was achieved in optimized devices, obtaining a new record efficiency with Pc-sensitized cells.

Electron-accepting phthalocyanine–pyrene conjugates: towards liquid phase exfoliation of graphite and photoactive nanohybrid formation with graphene

Herein, we describe the synthesis of a zinc(II) alkylsulfonylphthalocyanine–pyrene conjugate, its assembly with highly exfoliated graphite, and the investigation of the photophysical properties of the resulting nanohybrid. The presence of the pyrene unit in the conjugate is decisive in terms of non-covalently immobilizing the electron accepting phthalocyanines onto the basal plane of highly exfoliated graphite. As a matter of fact, strong interactions dominate the electronic properties of the nanohybrid in both the ground and excited states. For example, femtosecond pump probe experiments assist in corroborating an ultrafast charge separation, that is, the generation of the one-electron reduced radical anion of the phthalocyanine and one-electron oxidized graphene after irradiation at 387 nm, followed by slow charge recombination.