<p>Using Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT), the impact of auxiliary ligands such as aromatic heterocyclic and anchoring groups in Ru dyes on the performance of dye-sensitized solar cells (DSSCs) was reported. The designed dye was studied theoretically, including its geometric structure, electronic structure, and absorption spectrum. Then, quantum dynamics simulation was carried out, and the interfacial interaction and interfacial electron transfer processes of dye@TiO₂ were discussed. The results of the heterocyclic modification of the auxiliary ligands show that, on the one hand, the conjugated properties of the aromatic heterocyclic lead to the expansion of the light absorption range, and improve the ability to generate photocurrent. On the other hand, aromatic heterocyclic can also cause the distortion of the electronic structure of the dye, resulting in electron transfer difficulties. On this basis, dyes with the further introduced of cyanoacrylic acid (CA) anchoring group not only improved the unfavorable charge transport process and facilitated the downward electron transfer through aromatic heterocyclic, but also enhanced optical absorption properties. Additionally, its strong interfacial interaction with TiO₂ led to significant charge separation and rapid interface electron transfer (IET) rates. The aim of the study is to provide theoretical guidance for the design of candidate dyes for DSSCs.</p>