Computational Design and Optimization of Anthracene-Based Dyes for High-Efficiency Dye-Sensitized Solar Cells

Abstract

Developing competent dyes for dye-sensitized solar cells (DSSCs) is crucial for advancing the renewable energy transition. However, challenges such as efficiency, stability, and emission wavelength optimization remain significant hurdles. This research aims to improve solar cell conversion efficiency through the molecular engineering of dye molecules for DSSC applications. Applying Density Functional Theory (DFT) and Time-Dependent DFT (TDDFT) techniques, a known dye, AN-14, was modified with various electron donors, [Formula: see text]-spacers, and electron-withdrawing groups to produce eight novel dyes. Results reveal that all optimized dyes exhibit promising properties for solar cell application, including effective electron injection into the TiO 2 conduction band and efficient regeneration through the I[Formula: see text]/I[Formula: see text] redox couple. Among the engineered dyes, seven outperformed AN-14, exhibiting smaller energy gaps (E g ), enhanced absorption wavelengths (λ max ), and other significant photovoltaic parameters. Furthermore, chemical descriptors such as chemical hardness ([Formula: see text], electrophilicity index ([Formula: see text], electrodonating ([Formula: see text], and electroaccepting power ([Formula: see text] validate their suitability for DSSC purposes. Insights from photovoltaic properties, including light harvesting efficiency (LHE), open-circuit voltage (V oc ), excited-state lifetime ([Formula: see text], and excited-state energy (E dye ∗ ), further confirmed the reliability of these dyes. A detailed comparison of their optoelectronic properties suggests that dyes such as D2–D5 and D8 could exhibit superior DSSC performance compared to the other candidates. This study provides valuable insights for experimentalists in fabricating novel dyes with enhanced properties for advanced photovoltaic applications.