Anthracene-based perylene diimide electron-acceptor for fullerene-free organic solar cells

Non-fullerene electron-acceptor is an interesting class for advancement in organic solar cells. We herein report design and synthesis of An(PDI)2 which is composed of anthracene (An) as electron-rich core flanked with electron-deficient perylene diimide (PDI) to use in organic solar cells (OSCs) as an electron acceptor. The acceptor-donor-acceptor alternating structure afforded extended absorption range to 800 nm with suitable energy levels as an electron-acceptor. Despite An and PDI are highly conjugated molecules, An(PDI)2 possesses slightly twisted architecture, which would limit severe aggregation of the molecules. For the purpose to optimize power conversion efficiency (PCE) of OSCs using An(PDI)2, the morphology of the photoactive blend film was tuned by solvent mixture system. Through the careful optimization, the solar cell device achieved PCE up to 5.42% with a VOC of 0.83 V, a JSC of 10.88 mA/cm2 and FF of 0.60. This work suggests the potential of An(PDI)2 as a promising non-fullerene acceptor molecule to be utilized in OSC applications.