Bay Annulated Indigo as a New Chromophore for p-type Dye-Sensitized Solar Cells

A prototype bay-annulated indigo (BAI) dye has been synthesised and applied in p-type dye-sensitized solar cells (pDSC). The dye produced a broad spectral response up to 700 nm and an encouraging photocurrent (Jsc = 1.13 mA cm(-2), IPCE of 6.8%) was recorded. These results have highlighted several challenges for integrating BAI dyes into pDSCs, including: low dye loading, a tendency to aggregate and lack of built-in charge-transfer character, which can be overcome by simple modifications to the dye structure.