Enhancing DSSC Efficiency through Anchoring Group Engineering in D-A-π-A Sensitizers: A TD-DFT Investigation
نویسندگان
1 Laboratory of Analytical and Molecular Chemistry, Faculty of Sciences Ben M'Sik, Hassan II University of Casablanca, Casablanca, 7995, Morocco
2 Laboratory of Analytical and Molecular Chemistry, Faculty of Sciences Ben M'Sik, Hassan II University of Casablanca, Casablanca, 7995, Morocco
3 Laboratory of Analytical and Molecular Chemistry, Faculty of Sciences Ben M'Sik, Hassan II University of Casablanca, Casablanca, 7995, Morocco
4 Laboratory of Analytical and Molecular Chemistry, Faculty of Sciences Ben M'Sik, Hassan II University of Casablanca, Casablanca, 7995, Morocco
5 Laboratory of Advanced Materials and Applications (LM2A), Faculty of Sciences Dhar El Mahraz, Sidi Mohamed Ben Abdellah University, B.P.1796 Fez-Atlas, Morocco
6 Hassan II University of Casablanca, Morocco
doi
10.22036/pcr.2025.541704.2727چکیده
This study is based on Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TD-DFT) methods, using the CAM-B3LYP functional with the 6-31G(d,p) basis set, to investigate five D-A-π-A type organic dyes (COL1 to COL5) intended for dye-sensitized solar cells (DSSCs). Particular emphasis is placed on the influence of anchoring groups. The electronic properties, charge transfer mechanisms, and light absorption capabilities of the dyes were evaluated. Among the sensitizers studied, COL5, which incorporates a sulfur-rich heterocyclic anchoring group, stands out for its efficient intermolecular charge transfer, reduced excitation energy (narrow energy gap), and strong electronic coupling with the TiO_2 surface. In contrast, dyes such as COL2, which contain less effective anchoring groups, exhibit weaker interfacial interactions and wider energy gaps. The analysis of the balance between electron injection driving force and open-circuit voltage highlights the critical role of anchoring group design in optimizing photovoltaic performance. Additionally, calculations of reorganization energies and charge transfer dynamics confirm that electron-deficient anchoring groups contribute to minimizing energy losses. Overall, these findings offer valuable insights for the rational design of high-performance dyes, identifying COL5 as a promising candidate for experimental validation and device integration.
