Phosphine-mediated hydrogen bond and phosphorescence energy transfer for tunable chiroptical afterglow in stacked polymers
摘要
Polymer-doped chiral organic afterglow (COA) materials represent an emerging frontier in photonics, yet their development is constrained by weak hydrogen bond interactions and limited spectral diversity. Herein, a supramolecular engineering strategy utilizing phosphonic acid-derived directional hydrogen bond networks is proposed to construct COA materials. Leveraging the tetrahedral coordination geometry and dual proton-donor functionality of phosphonic acid derivatives, a robust three-dimensional hydrogen bond network is formed with polyvinyl alcohol, yielding blue afterglow emission with a lifetime of 3.05 s, a photoluminescence quantum yield of 33.3%, and enhanced thermal stability. Structural and computational analyses reveal that near-linear hydrogen bond geometry and orbital hybridization synergistically enhance the hydrogen bond strength while enabling chiral amplification by an interfacial chiral polylactic acid coating. Furthermore, through efficient phosphorescence energy transfer, multicolor COA emissions are achieved in stacked polymeric films, exhibiting dissymmetry factors up to 0.03 and afterglow emissions across the visible spectra, allowing the development of customizable encryption inks with spatiotemporal resolved chiroptical signatures for multiple applications. This work not only thoroughly investigates the modulation of hydrogen bonds on afterglow properties but also provides a fundamental understanding of non-covalent interactions in organic optoelectronics.