Research Information System
VII. International Joint Science Congress of Materials & Polymers, Gaziantep, Turkey, 10 - 13 October 2024, pp.44-45, (Summary Text)
Organic photovoltaic (OPV) materials have emerged as promising candidates for flexible, lightweight, and costeffective
solar cells. The design of donor-acceptor (D-A) molecules is crucial for optimizing OPV performance,
as it significantly affects key electronic properties such as HOMO-LUMO levels, open-circuit voltages (Voc),
and reorganization energies [1-3]. This study aims to investigate the electronic structures of D-A-D and A'-D-AD-
A' molecules, evaluate their potential for OPV applications, and assess the effects of various acceptor units
and cyano substitutions on their electronic properties. In the study, 6H-pyrrolo[3,4-b]pyrazine was used as the
donor unit and benzo[1,2-c:4,5-c']bis([1,2,5]thiadiazole) as the acceptor unit. Besides cyano substitutions,
various acceptor groups (A') such as phthalimide, benzotriazole, isoindole, and benzimidazole were also
incorporated into the molecular design. Density functional theory (DFT) calculations were employed to analyze
critical parameters, including HOMO-LUMO levels, open-circuit voltages, and reorganization energies. The
results revealed that the studied molecules exhibited low HOMO-LUMO gaps. Molecules containing
benzotriazole/isoindole, and cyano groups achieved open-circuit voltages exceeding 1V. Additionally,
reorganization energy calculations for the molecule with the highest open-circuit voltage indicated strong
potential for efficient electron transfer, especially in benzotriazole and cyano-containing molecules. These
findings suggest that the investigated molecules hold significant promise for highly efficient OPV devices and
offer valuable insights for future material design.