Photovoltaic properties and enhancement in near-infrared light absorption capabilities of acceptor materials for organic solar cell applications: A quantum chemical perspective via DFT

More than 22% power conversion efficiency (PCE) of organic solar cells (OSCs) has been reported with efficient narrow bandgap acceptor materials as the active layers. And end-capped modifications of such acceptor materials are an efficient approach for designing highly stable and efficient materials for organic solar cell applications. In this study, four new molecules ( TOS1 to TOS4 ) are designed for the active layer of organic solar cells. Density functional theory and time-dependent functional theory have been employed for the computation of various geometric, photovoltaic, optoelectronic properties of newly designed molecules. Different analyses like frontier molecular orbitals, transition density matrix, open-circuit voltage, absorption maxima, excitation and binding energies have been performed and examined with great care. Further, reorganization energy of hole and electron of novel designed molecules has been calculated and results suggested that designed systems are effective contributors for future development of organic solar cells. Overall, the outcomes of this study urge the experimentalists for the future development of highly stable and near-infrared absorbing organic solar cells. • More than 22% power conversion efficiency (PCE) has been achieved. • New molecules have been designed by end-capped modifications. • Efficient end-capped modifications in acceptor materials cause reduction in band gap. • Results of all the analyses suggested that the designed systems are efficient for organic solar cells.