Perylene Diimide‐based Non‐fullerene Acceptors With A‐D‐A′‐D‐A Architecture For Organic Solar Cells
Xiaoxiao You, Hao Shen, Qiang Wu, Yu Li, Di Wu, Jianlong Xia
Abstract
Abstract The vinylene‐bridged helical PDI dimer (PDI2) has been an alternative PDI building block for non‐fullerene acceptor (NFAs). However, the development of PDI2 derivatives still lag behind, and most of PDI2 derivatives based organic solar cells (OSCs) only achieved a moderate power conversion efficiencies (PCE) of less than 8%. In this contribution, an acceptor‐donor‐acceptor‐donor‐acceptor (A‐D‐A’‐D‐A) architecture was introduced to facilitate the improvement of photovoltaic properties. Two acceptors named diIDTIC‐PDI2 and diFIDTIC‐PDI2 were designed and synthesized, in which a PDI2 moiety flanked with two indacenodithiophene (IDT) units was employed as the D‐A’‐D core and 2‐(3‐oxo‐2,3‐dihydro‐1H‐inden‐1‐ylidene)malononitrile (IC) or fluorinated IC (IC2F) acted as terminal groups, respectively. The photovoltaic performances of these two acceptors were explored using PM1 as the electron donor. Compared to diIDTIC‐PDI2 , the fluorinated diFIDTIC‐PDI2 based OSCs obtained enhanced photovoltaic performance with the best PCE of 9.77%, a V OC of 0.957 V, J SC of 13.58 mA cm −2 and FF of 75.1%. These results illustrate that engineering terminal groups is a robust strategy of enhancing the efficiency of PDI based acceptors with A‐D‐A’‐D‐A architecture.