Design, Synthesis and Study of Dendrimers as Nanoscaffolds for Solar Energy Harvest

Designing molecules in which the vectorial motions of charges can be controlled has been of significant research interest in the recent past. Covalent linear arrays of chromophores or other molecular assemblies such as liquid crystals, zeolites, polymers, peptides, and amphiphiles have all been used as components for this purpose. Significant amount of this effort also involved the use of dendrimers as the molecular architecture. The structural feature in which multiple functionalities are present in the periphery that decreases gradually as one moves towards the core renders dendrimers obvious candidates for light harvesting antenna. Most of the efforts reported in the literature are directed towards energy funneling from a chromophore in the periphery to another chromophore at the core of the dendrimer. There are relatively few reports that utilize the dendritic architecture for photoinduced charge separation, an important step in designing materials for photovoltaics. These reports focus mostly on conjugated molecular backbones. Since non-conjugated dendrimer backbones provide the possibility of independently tuning the electronic characteristics of the chromophore and the charge transfer unit and therefore carry out a systematic structure-property relationship study, we have designed and synthesized dendrimer