Achiral isomers controlled circularly polarized luminescence in supramolecular hydrogels

Although chiral functional materials showing circularly polarized luminescence (CPL) are being widely reported, it remains a challenge to provide convenient and universal strategies for constructing controllable CPL-active materials with a high luminescence dissymmetry factor (g(lum)). Herein, the supramolecular chirality as well as the CPL handedness of phenylalanine-based hydrogels can be effectively regulated by commercial achiral naphthylamine isomers through non-covalent interactions. Typically, the co-assembled hydrogels exhibit considerably high |g(lum)| values in the range of 5.62 x 10(-3)-8.74 x 10(-3). The CPL inversion is mainly facilitated by intermolecular hydrogen bonds and pi-pi stacking between the achiral and chiral molecules, which might be induced by the reorientations of the assembled molecules. This work may provide an alternative method to construct tunable CPL-active materials.