Sterically hindered phthalocyanines for dye-sensitized solar cells: Influence of the distance between the aromatic core and the anchoring group

Abstract

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. Bulky for the best: A 5.57 % power-conversion efficiency is reached by a dye-sensitized solar cell constructed with TT58, that is, a new phthalocyanine (Pc) bearing bulky peripheral substituents and a carboxylic anchoring group directly attached to the macrocycle. Moreover, a Pc-sensitized solar-cell record efficiency of 6.49 % is attained with the previously reported TT40 by optimization of the conditions employed in the preparation of the devices. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.