Khalfan, Mwanahadia SalumBabu, Numbury SurendraVuai, Saidi A, H.2023-05-262023-05-262021Vuai, S. A., Khalfan, M. S., & Babu, N. S. (2021). DFT and TD-DFT studies for optoelectronic properties of coumarin based donor-π-acceptor (D-π-A) dyes: applications in dye-sensitized solar cells (DSSCS). Heliyon, 7(11).DOI: https://doi.org/10.1016/j.heliyon.2021.e08339http://hdl.handle.net/20.500.12661/4047Full text article. Also available at https://doi.org/10.1016/j.heliyon.2021.e08339A series of six coumarin based dye derivatives were investigated and their geometry and optoelectronic properties elucidated for suitability in dye-sensitized solar cells (DSSCs) using TD-DFT/B3LYP with 6-31G basis set. D-π-A schemes were developed by attaching various donors and acceptors to coumarin dye (CM) to calculate changes in their photovoltaic properties. D2-CM-A2 and D4-CM-A4 showed less dihedral angle because of the low steric effect between donor and connector. The D1-CM-A1 and D2-CM-A2 results of intramolecular charge transfer were higher because of low bond length and a strong group of electron donors. The results revealed that LUMO energies of D1-CM-A1, D2-CM-A2, D3-CM-A3 and D4-CM-A4 were higher than the conduction band edge of TiO2 electrode (-4.0 eV) suggesting that these dyes will inject the electrons into the conduction band of the semiconductor. In addition, the light harvest efficiency (LHE), open-circuit voltage (VOC) and band energy gap (Eg) values are calculated in the gas phase, as well as in the solvent phase. This study shows that D1-CM-D1 and D2-CM-A2 derivatives have better properties for application in the DSSCs.enOptoelectronic propertiesGeometry propertiesDye-sensitized solar cellsDSSCsCoumarin dyeDFT methodPhotovoltaic propertiesTD-DFT propertiesArticle