Effect of carboxylic acid and cyanoacrylic acid as anchoring groups on Coumarin 6 dye for dye-sensitized solar cells: DFT and TD-DFT study

Abstract Starting with Coumarin-6 dye, two novel D-π-A organic dyes C6X and C6N have been designed by attaching carboxylic acid cyanoacrylic groups as anchoring to Coumarn-6 respectively, understand their potential use in dye-sensitized solar cells (DSSCs). The electronic structure photophysical photovoltaic properties of the were studied using density functional theory DFT time-dependent TD-DFT Becke3-Parameter-Lee–Yang–Parr (B3LYP) 6-31G (d, p) basis set. Optimized (highest occupied molecular orbital energy (E HOMO ), lowest unoccupied LUMO difference g ) between LUMO) calculated showing that has smallest band gap larger absorption region. Density states (DOS), electrostatic (MEP), natural bond (NBO) analysis, non-linear optical (NLO) properties, UV–vis spectra, well some crucial parameters affecting performance DSSCs, such light-harvesting efficiency (LHE), electron injection driving force (ΔG inject dye regeneration force(ΔG reg excited state life time(τ e study effect group on DSSC performance. Additionally, adsorption TiO2 anatase (101) surface mechanism also investigated a dye–(TiO 2 9 cluster model TD-B3LYP calculation. energies suggest strong TiO surface. results show may be theoretically good candidate sensitizer application.