Non-fullerene fused-ring electron acceptors boost the power conversion efficiency of organic
solar cells, but they suffer from high synthetic cost and low yield. Here, we show a series of
low-cost noncovalently fused-ring electron acceptors, which consist of a ladder-like core
locked by noncovalent sulfur–oxygen interactions and flanked by two dicyanoindanone
electron-withdrawing groups. Compared with that of similar but unfused acceptor, the
presence of ladder-like structure markedly broadens the absorption to the near-infrared …