Chiral Memory-Driven Helical Supramolecular Photodetector for Deciphering Circularly Polarized Light

Chiral π-conjugated organic small molecules, due to their intrinsic chirality, well-defined molecular structures and ease of modification, are promising for circularly polarized light (CPL) detection. However, their practical application is hindered by low absorption dissymmetry factor (g_abs), arising from imbalanced electric and magnetic transition dipole moments (µ and m). Here, a template-free method using chiral memory effect was reported to fabricate helical supramolecules with high g_abs. Two chiral dinaphthocoronene tetraimides enantiomer pairs were synthesized: (R)-PDI-(R)-NI-Ph/(S)-PDI-(S)-NI-Ph and (S)-PDI-(R)-NI-Ph/(R)-PDI-(S)-NI-Ph. After annealing films at 350°C to remove chiral pendants, (R)-PDI-(R)-NI/(S)-PDI-(S)-NI films showed much higher |g_abs| (0.08) than the other set (0.01), with helical assemblies formed via chiral memory effect. Notably, large-area arrays of (R)-PDI-(R)-NI films enabled CPL imaging, and a bionic artificial visual system was constructed with this film as "retina" and an artificial neural network as "neural center" for reliable CPL discrimination, offering a scalable strategy for high-performance chiral optoelectronics.