Panchromatic symmetrical squaraines: a step forward in the molecular engineering of low cost blue-greenish sensitizers for dye-sensitized solar cells

Two novel symmetrical blue squaraine sensitizers were synthesized, which exhibit panchromatic light harvesting and a record efficiency over 6% with J(sc) exceeding 14 mA cm(-2), and V-oc over 620 mV under 1 sun. Their color, low cost, easiness of synthesis, and relatively high photo- and thermal stability open up the way for commercial applications.