Influence of heteroatoms on the optoelectronic properties of triphenylamine-based dyes for DSSCs application: A computational approach

A series of sensitizers with D-pi-pi-A architectural framework have been fine-tuned through a variation of het-eroatoms (NH, O, Se, and Te) in the pi-spacers. Cyanoacrylic acid and hydantoin were used as the acceptor groups. The geometrical and electronic properties were investigated through density functional theory (DFT) and time-dependent DFT (TD-DFT) , respectively. To determine stable dye-TiO2 configuration, the binding energies are reported. The driving force of charge injection and dye regeneration range between 0.00 to -0.77 eV and -0.133 to -1.60 eV, respectively, suggesting spontaneous processes. Chalcogen heteroatoms (S, Se, and Te) improved absorption within the visible and NIR regions. The binding energies of dye on (TiO2)(6) cluster range between -8.32 to -9.62 eV and -7.77 to-8.98 eV for cyanoacrylic acid and hydantoin dyes, respectively. The findings suggest that the inclusion Se and Te heteroatoms may boost the performance of DSSCs when compared to parent materials containing S.

Automated summary

A series of sensitizers with D-pi-pi-A architectural framework have been fine-tuned through the variation of heteroatoms in the pi-spacers. The geometrical and electronic properties were investigated, and it was found that chalcogen heteroatoms improved absorption. The binding energies of sensitizers on the dye-TiO2 interface were stable.