Implanting Lanthanide Luminophores Into Helical Scaffolds for Programmable Circularly Polarized Luminescence

Abstract

ABSTRACT Integrating achiral luminophores into chiral supramolecular helices represents a promising route to strong circularly polarized luminescence (CPL). However, for lanthanide systems, efficient emitter loading and effective chirality induction remain challenging due to weak host–guest interactions and the shielded nature of 4f electrons. Herein, we report a supramolecular chelation strategy that implants Eu 3+ emitters into pre‑assembled helical nanoribbons (HNRs), enabling efficient chirality induction and tunable CPL brightness. Two cholesterol–terpyridine conjugates, differing only in their linker chemistry (ester vs. carbonate), demonstrate that the ester linker promotes long‑range chirality induction and HNR formation, whereas the carbonate counterpart yields achiral aggregates. Moreover, the assembly sequence is crucial: pre‑formation of the helical scaffold preserves the non‑covalent network necessary for effective chirality induction, whereas prior metal coordination introduces steric hindrance that disrupts chiral order. The resulting systems exhibit orthogonal luminescence responses: Eu 3+ ‑loaded assemblies are humidity‑sensitive but thermally stable, while β ‑diketonate‑shielded analogues are temperature‑responsive yet humidity‑resistant, allowing multi‑level information encryption. By introducing this modular “assemble‑then‑coordinate” approach, we provide new insights into supramolecular chirality induction and open avenues toward advanced, stimulus‑responsive CPL materials.