Muhammad Arvito Ramadhan, Okta Suryani, Lala Adetia Marlina, Aulia Sukma Hutama, Suci Zulaikha Hildayani, Trisna Kumala Sari, Riga Riga, Hanif Sabawi Ma'ruf
Density functional theory (DFT) and time-dependent DFT (TD-DFT) were used to investigate the use of the BODIPY–coumarin derivatives as dual-functional photosensitizers for dye-sensitized solar cells and photocatalytic hydrogen evolution. Halogen substitution at the 2,6-positions (F, Cl, Br, and I) and anchoring group engineering have been studied to tune the electronic structure, intramolecular charge transfer (ICT), and optical properties. All systems maintain quasi-planar donor– π–acceptor (D–π–A) frameworks with extended π-conjugation. Fluorinated derivatives exhibit the smallest HOMO–LUMO gaps (∼3.92 eV), whereas strong electron-withdrawing anchors enhance the acceptor strength and induce red-shifted absorption. TD-DFT predicted two main absorption bands at 370–417 and 575–636 nm, with the largest bathochromic shifts observed for BDP3-F (636 nm) and BDP2-F (635 nm). Calculated free energies indicate favorable electron injection (ΔGinj ≈ −0.19 to −0.28 eV) and dye regeneration (ΔGreg ≈ −0.66 to −0.82 eV), with moderate reorganization energies. Overall, BDP2-F and BDP3-F are the most promising candidates. © 2024
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Negeri Padang, Padang, 25132, Indonesia; Research Center for Computing, National Research and Innovation Agency (BRIN), Cibinong, Bogor, 16911, Indonesia; Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Yogyakarta, 55281, Indonesia
