Theoretical Modification on The Structure of Dithiophene-Based Dyes as Sensitizers In Solar Cells

One of the key parameters in designing DSSCs is the dye, which plays a crucial role in absorbing light. This study aims to modify the structure of D-π-A type dyes based on dithiophene with variations in the donor chain. The donor chains used were phenol, aniline, indoline, diphenylamine, coumarin, and toluene, symbolized as T1, T2, T3, T4, T5, and T6. The acceptor chain used was cyanoacetic acid. Calculations were performed using the Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT) methods with the B3LYP/6-31G basis set. The study results indicated that all modified dyes were potential sensitizers because they can absorb light in the visible to infrared (IR) regions. The T3 dye, with an indoline donor chain, was the best dye to be used as a sensitizer, with a bandgap value of 1.7149 eV, a maximum wavelength (λ) of 939.43 nm, excitation energy of 1.3198 eV, ΔGinj of -04250 eV, ΔGreg of 0.0948 eV, and a VOC value of 08201 eV