Supramolecular architectures featuring the antenna effect in solid state DSSCs

Hybrid artificial antenna systems, with implementation of nature's basic concept of self-organization of chromophores, attract vast interest due to their potential application in solar cells. Herein, we report a new supramolecular system comprising two porphyrins, a free base and its zinc analogue, bearing diphenylalanine units. The first is grafted on the TiO2 surface and plays the role of an initiator in the self-assembly of the second, inducing the formation of multi-molecular self-assembled spherical nanostructures. The achieved assemblies display an antenna effect and are used as biomimetic chromophore systems for dye-sensitized solar cells (DSSCs). This self-assembled antenna system gives a proof of concept that multichromophoric supramolecular assemblies based on hydrogen bonds can be of practical use for photovoltaic applications.