Ricerc@Sapienza

The application of four pyran based dyes as sensitizers for p-type dye-sensitized solar cells (p-DSCs) is here
proposed. The dyes differ for the nature of the electron acceptor group which functionalizes the pyran core. Such
a structural variation significantly influences the optical properties of the dyes so that the new pyrans overall
cover most of the visible spectrum. In some cases, the p-DSCs employing these pyran-based dyes display power
conversion efficiency significantly higher than the device sensitized with sensitizer benchmark P1. The relevant

Three different pyran based dyes were synthesized and tested for the first time as photosensitizers of NiO based p-type dye-sensitized solar cells (p-DSSC). The molecules feature a similar molecular structure and are based on a pyran core that is functionalized with electron acceptor groups of different strength and is symmetrically coupled to phenothiazine donor branches. Optical properties of the dyes are deeply influenced by the nature of the electron-acceptor group, so that the overall absorption of the three dyes covers the most of the visible spectrum.