Covalent and Noncovalent Phthalocyanine-Carbon Nanostructure Systems: Synthesis, Photoinduced Electron Transfer, and Application to Molecular Photovoltaics

The tunable absorption features of phthalocyanine (Pcs) and related compounds such as subphthalocyanines (SubPcs) render them ideal antenna systems that harvest light over a broad range of the solar spectrum. The different synthetic strategies that have been pursued so far for the preparation of D-A Pc and SubPc-carbon nanostructure systems, having the donor and the acceptor units connected either covalently or by using supramolecular interactions were studied. A thorough analysis on the photophysical properties of dyads in solution was also carried out, confirming the occurrence of PET events. Transmission electron microscopy (TEM) studies revealed that the amphiphilic Pc-C60 dyad salt, when dispersed in water, is able to form perfectly ordered 1-D nanotubules, due to a combination of solvophobic and π-π stacking interactions. One of the most outstanding applications of these materials is their incorporation in photovoltaic devices in which generation of electrical current from solar energy takes place.