Synthesis of NIR Rylene Dyes and Cobalt-based Redox Couple for Colourless Dye-sensitized Solar Cells

Photovoltaic cells (PV) assembled with semiconductor technology techniques are, nowadays, the most efficient systems for solar energy conversion.1,2 Dye-Sensitized Solar Cells (DSSCs) represent one of the best performing technologies developed in the last decades to overcome the limitations of the well-known silicon-based photovoltaics cells 1,2. Building Integrated PhotoVoltaics (BIPV) based on DSSC are a promising application to make DSSC more attractive in the energy production field. An innovative approach resides on the implementation of a new class of colourless DSSCs based on NIR rylene dyes along with transparent cobalt complexes based redox couples.3,4 In this work, we will stepwise extend the rylene aromatic core to tune the electronical properties of the dyes, while introducing various substituents on the bay positions to improve the processability properties of the final materials. On the other side, di, ter-pyridine-based ligands, decorated with various substituents, will be synthetized to produce a large library of cobalt (II) complexes as redox mediator for BIPV devices. The overall properties of the dyes and complexes will be investigated and modulated to achieve the photophysical and electronical requirements to assembly innovative devices able to shorten the gap with the silicon-based photovoltaic cells.