Spatially confined single-molecule folding achieves multicolor phosphorescence.

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Organic Electronics

Background:

• Supramolecular polymers offer unique properties through self-assembly.
• Controlling photophysical properties like phosphorescence is crucial for advanced materials.
• Macrocyclic hosts like cucurbiturils can template complex structures.

Purpose of the Study:

• To synthesize a pure organic supramolecular polymer with tunable near-infrared phosphorescence.
• To investigate the role of macrocyclic confinement and polymerization in inducing specific photophysical properties.
• To explore the potential of these materials for dynamic information encryption.

Main Methods:

• Encapsulation of triphenylamine derivatives within cucurbit[8]uril (CB[8]) to form biaxial pseudorotaxanes.
• Oriented polymerization of exposed ethylene units with acrylamide to create supramolecular polymers (p-TAPCB).
• Tuning phosphorescence properties by adjusting CB[8] ratio and employing phosphorescence resonance energy transfer (PRET) with TPE donors.

Main Results:

• A pure organic supramolecular polymer (p-TAPCB) exhibiting near-infrared room-temperature phosphorescence (NIR RTP) with high quantum yield (47.03%).
• Tunable phosphorescence color achieved by varying the CB[8] ratio, dependent on excitation wavelength and concentration.
• NIR emission lifetime flexibly manipulated from 9.87 ms to 1490 ms using PRET, with a large Stokes shift (390 nm).

Conclusions:

• Macrocyclic confinement and polymerization synergistically induce high-efficiency NIR RTP in supramolecular polymers.
• The developed materials possess tunable emission color and controllable lifetime, suitable for dynamic information encryption.
• This work presents a versatile platform for designing advanced functional supramolecular materials.