Porphyrin (Por) and phthalocyanine (Pc) dyes have been received worldwide efforts by researchers for powerful technological and biomedical applications. These dyes were strongly employed in photodynamic therapy, solar light-harvesting materials, and nanosciences. Nanosciences and nanotechnologies have attracted large importance due the photochemical and photophysical properties of resulting hybrid materials. In these fields, the investigators have explored carbon allotropes mainly fullerenes (C60 or e.g. PyC60, Figure 1), carbon nanotubes and graphene (Figures 2 and 3) due to their matchless electronic features. From the carbon nanomaterials, graphene is the most exciting material in the technological applications due to its conductivity, photonic and optoelectronic features reported in solar cells, light-emitting devices, touch screens, etc.
Graphene shows considerable challenges due to its lack solubility, where the supramolecular derivatization and exfoliation methods are able to individualize, solubilize and/or disperse them in solution. Noncovalent functionalization of graphene with dyes (via pi-pi-stacking or van der Waals interactions) have been providing remarkable assembly methods due to the electronic preservation. Thus, we propose to connect supramolecularly the carbon structures with the optical properties of the dyes for optoelectronic applications. In particular, we are interested in to synthesize Pors and Pcs with anchoring groups for molecular recognition of graphene and/or PyC60. Thus, Pors and Pcs with imidazole- or imidazolium-pyrene synthons (Schemes 2-4), and 1st and 2nd generation of pyrene-dendritic Pors and Pcs (Schemes 5-10) will be synthetized and interacted supramolecularly with graphene or PyC60 (Figures 5 and 6) to perform new electron donor-acceptor nanomaterials. The photophysical properties of these materials and their individual components will be evaluated and managed in collaboration with Prof. Guldi. We will also make efforts to encouraging their use in energy, environment and electronic fields.
Requirements to create efficient light converting systems are strong light absorption, capacity to funnel excited state energy by energy transfer, and photoinduced electron transfer process (Figure 4). In this project, Pors and Pcs with dendritic pyrenes (Figures 5 and 6, Schemes 5-10) for supramolecular functionalization of carbon structures will be prepared and characterized. These dyes harvester solar light disclose high cell performance comparable to that of known ruthenium complexes. These properties endeavour their effective use in dye-sensitized solar cells as organic dyes without metals or with more environmentally safer metals than ruthenium. The electronic performance efficiency of the chromophoric components with larger absorption, aggregation/dispersion, photostability, redox potentials, etc., will be studied.