Computational Screening of Organic Dye-Sensitizers for Dye-Sensitized Solar Cells: DFT/TDDFT Approach

Dye-sensitized solar cells (DSSCs) represent a promising third-generation photovoltaic technology due to their ease in fabrication, low cost, ability to operate in diffused light, flexibility, and being lightweight. Organic dye-sensitizers are vital components of the DSSCs. Comprehensive theoretical study of the dye’s spectroscopic properties, including excitation energies ground- and excited-state oxidation potential, allows to design and screen organic dye-sensitizers for an efficient DSSC. Density functional theory (DFT) and time-dependent DFT (TDDFT) approaches have been efficiently used to estimate different optoelectronic properties of sensitizers. This chapter outlined the use of the DFT and TDDFT framework to design organic dye-sensitizers for DSSCs to predict different photophysical properties. Prediction of essential factors such as short-circuit current density (J_SC ), open-circuit voltage (V_OC ), along with charge transfer phenomena, will help experimental groups to fabricate DSSCs with higher photoconversion efficiency (PCE). Besides, this chapter includes a basic understanding of the mechanism of DSSCs, based on the energetics of the various constituents of the heterogeneous device.