DFT based modeling of asymmetric non-fullerene acceptors for high-performance organic solar cell

Abstract

In this study, five new asymmetrical fullerene-free acceptor molecules (N1 to N5) have been designed for organic solar cell applications. Density functional theory and time dependent density functional theory has been employed for exploring the opto-electronic, photovoltaic and geometric properties of the designed molecules. A narrow energy band gap with high red-shifting in the absorption spectrum has been noted. High open circuit voltage with good values of reorganizational energy of electron suggested that designed molecules are effective contributor for solar cell applications. Transition density matrix and frontier molecular orbitals analysis also expressed the presence of charge density within a molecule with different types of transitions. Finally, blend study also performed for exploring the charge transfer between donor polymer and acceptor molecule.