Dithienogermole-containing D–π–A–π–A Photosensitizers for Dye-sensitized Solar Cells

Recently, we prepared D–π1–A1–π2–A2-type dyes, containing dithienogermole (DTG) as π1-spacer, and demonstrated their use as DSSC sensitizers. In this study, alkoxy units were introduced on the triphenylamine D fragment, which would enhance the hydrophobicity on the TiO2 surface in DSSC. We also introduced a benzene ring as the π2-spacer, in place of thiophene to control the energy levels. Recently, we prepared D–π1–A1–π2–A2-type dyes, containing dithienogermole (DTG) as π1-spacer, and demonstrated their use as DSSC sensitizers. In this study, alkoxy units were introduced on the triphenylamine fragment, which would enhance the hydrophobicity on TiO2 surface in DSSC. We also introduced benzene ring as the π2-spacer, in place of thiophene to control the energy levels.