New organic sensitizers with improved spectral properties for application in greenhouse-integrated Dye-Sensitized Solar Cells

Nowadays, the development of photovoltaic greenhouses represents a smart tool for increasing sustainability in agricultural production. However, the first target of a greenhouse is the growth of plants, so their proper illumination is crucial. For this reason, the choice of the proper solar technology should be led by the transparency and the color versatility of the devices and both these properties are actually satisfied by DSSCs (Dye-Sensitized Solar Cells). In the last years, we have been interested in the synthesis of new D-p-A organic dyes showing an intense light absorption and especially suitable to build transparent thin-layer DSSCs. Starting from these compounds, which are based on a thiazolo[5,4-d]thiazole scaffold, we decided to synthesize a new series of photosensitizers specifically designed for greenhouses application. The aim was to minimize the light absorption in that part of the spectrum used for photosynthesis and, consequently, to warrant the proper growth of the plants. A robust Pd-catalyzed direct arylation protocol was developed, in order to introduce selective modification on the dye structure and to prepare dyes on grams-scale.