Computational Molecular Design of New 3D Structured Quinoxaline Dyes With Panchromatic NIR Absorption and Enhanced Stability Enabling Efficient Copper-Based Dye Sensitized Solar Cells.

This research computationally designed and evaluated new quinoxaline-based dyes for copper-based dye-sensitized solar cells (Cu-DSSCs). Using DFT/TDDFT calculations, the team found that dyes incorporating pyrazino[2,3-g]quinoxaline groups exhibited significantly improved light-harvesting abilities, with an NIR absorption spectrum spanning the entire UV-visible range. These dyes maintained charge transfer characteristics comparable to the champion dye ZS4, leading to a maximum photocurrent density enhancement of 11.5 mA/cm2. Importantly, the use of heterocyclic anchoring groups substantially increased adsorption stability. The researchers identified the pyrazino[2,3-g]quinoxaline-cyclopenta[1,2-b:5,4-b']dithiophene-2-(1,1-dicyanomethylene) combination as superior to ZS4, paving the way for more efficient and stable Cu-DSSCs.