​Ruthenium-based polypyridine complexes are excellent photosensitizers due to their strong light absorption and efficient electron transfer, making them highly effective in solar energy applications with conversion efficiencies up to 11%. However, ruthenium is expensive, toxic, and scarce, making it impractical for large-scale use. As a result, researchers are looking for more affordable, abundant, and environmentally friendly alternatives, such as iron.
Traditional iron(II) polypyridyl complexes show strong absorption but suffer from fast deactivation of their excited states, which prevents efficient electron injection into solar cell materials. This quick loss of energy limits their ability to convert light into usable energy. The lifetime of these excited states depends on factors like the strength of the ligands surrounding the iron and the structure of the ligands, which affect the energy of the excited states.
This project focuses on predicting how different molecular setups of iron polypyridyl complexes behave in terms of excited-state energies, how long they last, and how they interact with semiconductor materials like TiO₂. The goal is to better understand and improve the efficiency of dye-sensitized solar cells by optimizing these excited-state properties.