Advancing optoelectronic performance of organic solar cells: Computational modeling of non-fullerene donor based on end-capped triphenyldiamine (TPDA) molecules

Abstract

In this study, quantum chemical and density functional theory (DFT) methods were used to investigate triphenyldiamine-based molecules for enhancing organic solar cells (OSCs). A reference molecule (XSln84) [(E)-2′-methoxy-N4,N4,N4″,N4″-tetrakis(4-methoxyphenyl)-5′-(4-methoxystyryl)-[1,1′:3′,1″-terphenyl]-4,4″-diamine)] and six modified molecules (A1 to A6) were analyzed. The molecular properties of these molecules were thoroughly investigated, including maximum absorption wavelength (λmax), frontier molecular orbitals (FMO), and quantum chemical parameters. A4 showed excellent miscibility, highest absorption wavelength, small energy gap, and high dipole moment in dichloromethane DCM solvent. Compared to the reference molecule, all modified molecules exhibited higher estimated open-circuit voltage (VOC) and remarkable power conversion efficiency (PCE), with A5 having the highest PCE. A3 had the highest electron mobility, while A6 showed the highest hole mobility. The end-capped modifications improved the optoelectronic properties, suggesting potential for efficient OSCs. These findings contribute to understanding these molecules and their renewable energy applications, benefiting the field of organic solar cells.