A screening of properties and application based on dimerized fused-ring non-fullerene acceptors: influence of CC, C–C, spiro-C linkers

Material application functions, such as film morphology and environmental friendliness, have proved to be crucial for the power conversion efficiencies (PCEs) of organic photovoltaics (OPVs), thus attracting greater attention. Therefore, it is necessary to extend the relationship between structure and property to structure and applicability. In the present study, we employ a series of dimerized fluorene molecules with different linkers (CC, C–C, spiro-C) to explore the relatedness of chemical bond → material functionality → applicability through DFT/TD-DFT and MD methods. The results showed that bridge valence bond type determines the specific function, such as orbital degeneracy and singlet fission, while the twist angle between fused-ring fragments determine the material functionality, film morphology and solvent selectivity (environmental friendliness). Moreover, based on the regular effects of the above parameters, specific properties and application functions could be obtained through targeted molecular designs. This insight and discovery are expected to bring inspiration for material application designs and the development of other related materials.