Achiral isomers controlled circularly polarized luminescence in supramolecular hydrogels

Abstract

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 × 10⁻³–8.74 × 10⁻³. The CPL inversion is mainly facilitated by intermolecular hydrogen bonds and π–π 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.