Tunable Reversible Photochromic Ultralong Organic Phosphorescence via a Universal Phenylpyridine Noncovalent Assembly
Xue Bai1, Renliang Wang1, Hong-Jin Xue2
1School of Chemistry and Pharmaceutical Engineering, Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, China.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|July 21, 2026
Summary
Researchers developed a universal method using phenylpyridine derivatives and α-cyclodextrin to create supramolecular materials with switchable photochromism and ultralong organic phosphorescence (UOP). This enables advanced applications in information encryption and photopatterning.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Photonic Materials
Background:
- Photochromic materials change color reversibly with light.
- Ultralong organic phosphorescence (UOP) involves light emission from triplet states with long lifetimes.
- Developing materials with both properties is challenging.
Purpose of the Study:
- To create a universal supramolecular assembly strategy for simultaneous photochromism and UOP.
- To investigate the underlying mechanisms of dual photo-responsive behavior.
- To explore potential applications in information storage and patterning.
Main Methods:
- Utilized linear phenylpyridine derivatives and α-cyclodextrin for supramolecular assembly.
- Employed multivalent interactions (host-guest complexation, hydrogen bonding) to form a noncovalent network.
- Investigated photoinduced electron transfer and radical generation for photochromism.
Main Results:
- Achieved simultaneous switchable photochromism and UOP in the solid state.
- Observed a maximum phosphorescence lifetime of 0.96 s and quantum yield of 53.1%.
- Demonstrated dynamic regulation of UOP via a photoinduced radical-mediated photochromic switch.
- Enabled tailorable phosphorescent performance and multicolor photochromism through molecular engineering.
Conclusions:
- Presented a facile and universal supramolecular strategy for multifunctional photo-responsive materials.
- Highlighted the potential for multistage information encryption and time-resolved photopatterning.
- Opened new avenues for advanced photonic applications using green supramolecular approaches.
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