In summary, the A–D–A type acceptors, with higher electronmobility in the range of 104 to 103 cm2 V1 s1, have alsomade rapid progress recently for their distinctive superiorities.Tens of A–D–A type NFAs have been developed so far, some ofthem have presented much better performance than PDIs.Through modifying the core units, side chains, spacers and theend-groups, the molecular structure, thus material properties ofthe NFAs can be readily tuned.