Theoretical Studies and Photovoltaic Performance of 1,10- Phenanthroline Derivative Compound as a Multiple Anchor Group

In this study, organic dyes (B1 and B3) with a D–π–A architecture were synthesized for use in dye-sensitized solar cells (DSSCs). The molecules were designed with triphenylamine as the electron donor, an imidazole bridge, and 1,10-phenanthroline as an anchoring unit to facilitate efficient electron transfer to the semiconductor (TiO₂) surface. The multi-anchor structure of B3 was intended to enhance power conversion efficiency (PCE) by enabling more efficient electron injection from the donor group to the semiconductor. Structural characterization of the dyes was performed using FT-IR, NMR, mass spectrometry, UV-Vis spectroscopy, and electrochemical measurements. Theoretical calculations were performed using the density functional theory (DFT) method with the 6-31G(d)/LANL2DZ basis set. Theoretical analysis revealed that lower band gap energy would facilitate electron transfer between the HOMO and LUMO levels, thus potentially increasing PCE values. The B3 compound exhibited a lower band gap energy compared to B1. The DSSC device incorporating the multi-anchor B3 dye achieved higher power conversion efficiency than the device containing the single-anchor B1 dye. Photovoltaic measurements showed that the DSSC device incorporating B3 achieved a PCE of 0.61%, whereas the device with B1 reached a PCE of 0.28%. The obtained results showed that B3 compound possesses promising structural properties for photovoltaic applications.