Molecular Dynamics Simulation as a Tool for Studying the Solvent in the Dye/TiO2 Interaction in Natural Dye Sensitized Solar Cells

Abstract

- The present work focuses on studying the interaction between a natural dye, cyanidin-3-glucoside, and the TiO2 surface in sensitized solar cells. Molecular dynamics simulations based on the reactive force field ReaxFF were employed to investigate these interactions. Various solvent environments based on water and ethanol proportions were examined. The simulation results reveal that dye chemisorption always occurs, but with differences depending on the solvent used. A more favorable stability and Ti-O bond distance were observed in systems with solvent ratios of 1:1 and 1:3, suggesting improved dye loading under these conditions. Additionally, sensitized solar cells were prepared using the same solvents utilized in the simulation, and current-voltage and IPCE measurements were performed. It was found that cells prepared with the more stable solvent ratios exhibit higher photocurrent and efficiency. Overall, the results from the molecular simulation are in agreement with the experimental data, indicating its potential for predicting the optimal solvents to use in the preparation of natural dyes based on anthocyanins.