Achieving efficient green-solvent-processed organic solar cells by employing ortho-ortho perylene diimide dimer

The lack of electron acceptors with suitable green solvent processing and excellent device performance is an important problem that hinders the development and commercialization of organic solar cells (OSCs). Here, an ortho-ortho perylene diimide (PDI) dimer (oo-2PDI) is developed and used as an acceptor for use in efficient green-solvent-processed (GSP) OSCs. By using chlorobenzene (CB), anisole, and ortho-xylene as the processing solvents, power conversion efficiencies (PCEs) of 5.04%, 5.03%, and 5.78% were achieved without the additive, respectively. In addition, the non-fullerene oo-2PDI-based GSPOSCs show superior photovoltaic performance to [6,6]-phenyl-C61-butyric acid methyl ester (PCBM)-based GSPOSCs under identical conditions. Therefore, these results demonstrate the possibility of achieving efficient non-fullerene GSPOSCs.