title: An electro-optical and electron injection study of benzothiazole-based squaraine dyes as efficient dye-sensitized solar cell materials: a first principles study.
abstract: Squaraine dyes have attracted significant attention in many areas of daily life from biomedical imaging to semiconducting materials. Moreover, these dyes are used as photoactive materials in the field of solar cells. In the present study, we investigated the structural, electronic, photophysical, and charge transport properties of six benzothiazole-based squaraine dyes (Cis-SQ1-Cis-SQ3 and Trans-SQ1-Trans-SQ3). The effect of electron donating (-OCH3) and electron withdrawing (-COOH) groups was investigated intensively. Ground state geometry and frequency calculations were performed by applying density functional theory (DFT) at B3LYP/6-31G** level of theory. Absorption spectra were computed in chloroform at the time-dependent DFT/B3LYP/6-31G** level of theory. The driving force of electron injection (ΔG (inject)), relative driving force of electron injection (ΔG r (inject)), electronic coupling constants (|VRP|) and light harvesting efficiency (LHE) of all six compounds were calculated and compared with previously studied sensitizers. The ΔG (inject), ΔG r (inject) and |VRP| of all six compounds revealed that these sensitizers would be efficient dye-sensitized solar cell materials. Cis/Trans-SQ3 exhibited superior LHE as compared to other derivatives. The Cis/Trans geometric effect was studied and discussed with regard to electro-optical and charge transport properties.
authors.affiliation: Chemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203, Jeddah, 21589, Saudi Arabia.
authors.forename: Najat Saeed
authors.initials: NS
authors.lastname: Al-Fahdan
authors.forename: Abdullah M
authors.initials: AM
authors.lastname: Asiri
authors.forename: Ahmad
authors.initials: A
authors.lastname: Irfan
authors.forename: Salem A
authors.initials: SA
authors.lastname: Basaif
authors.forename: Reda M
authors.initials: RM
authors.lastname: El-Shishtawy
mesh_terms: D052160:Benzothiazoles / Q000737:chemistry / Q000528:radiation effects*; D004396:Coloring Agents / Q000737:chemistry / Q000528:radiation effects*; D003503:Cyclobutanes / Q000737:chemistry / Q000528:radiation effects*; D055664:Electrochemical Techniques; D004583:Electrons; D004735:Energy Transfer; D008027:Light; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D055095:Optics and Photonics / Q000379:methods*; D010084:Oxidation-Reduction; D010636:Phenols / Q000737:chemistry / Q000528:radiation effects*; D012993:Solar Energy; D013057:Spectrum Analysis; D013329:Structure-Activity Relationship
chemical_list: D052160:Benzothiazoles; D004396:Coloring Agents; D003503:Cyclobutanes; D010636:Phenols; C480596:squaraine; C005465:benzothiazole