Benzyl side-chain engineering of non-fullerene acceptors for efficient organic solar cells

Side-chain engineering is one of the most promising ways to develop non-fullerene acceptors (NFAs) for organic solar cells. In this work, we designed and synthesized a novel acceptor IT-BnC6-4F by introducing methylene group between the phenyl group and the sp(3) hybrid carbon atoms of central conjugated cores to form benzyl side chains. IT-BnC6-4F shows broader absorption spectrum and higher crystallinity than those of its analogue, IT-4F. When blended with PT2, the IT-BnC6-4F based device achieved a high power conversion efficiency (PCE) of 13.36 %, with an open-circuit voltage (V-oc) of 0.87 V and a short-circuit current density (J(sc)) of 20.99 mA cm(-2).

Automated summary

Side-chain engineering is an effective way to develop non-fullerene acceptors for organic solar cells. A novel acceptor IT-BnC6-4F was designed and synthesized in this work, which showed a broader absorption spectrum and higher crystallinity than its analogue IT-4F. When blended with PT2, the IT-BnC6-4F based device achieved a high power conversion efficiency of 13.36%.