Supramolecular Pins with Ultralong Efficient Phosphorescence.

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Organic Electronics

Background:

• Developing ultralong organic phosphorescent materials with high quantum yields presents significant challenges.
• Existing supramolecular binding strategies often face limitations like electrostatic repulsion and inefficient charge transfer.

Purpose of the Study:

• To design and synthesize novel purely organic supramolecular pins for high-performance phosphorescent materials.
• To investigate a new supramolecular binding mode for enhanced intramolecular charge transfer and overcome electrostatic repulsion.
• To explore the application of these materials in multicolor photoluminescence and targeted biological imaging.

Main Methods:

• Supramolecular assembly of alkyl-bridged phenylpyridinium salts with cucurbit[8]uril (CB[8]).
• Characterization of binding modes ('one host with one guest', 'head-to-head').
• Measurement of phosphorescence quantum yield and photoluminescence properties.
• Incorporation into rigid matrices and application in mitochondria imaging.

Main Results:

• A novel 'one host with one guest' and 'head-to-head' supramolecular binding formation was achieved.
• The supramolecular pin 1/CB[8] complex exhibited an exceptionally high phosphorescence quantum yield of 99.38% in a rigid matrix.
• Multicolor photoluminescence was demonstrated by varying excitation wavelengths and host-guest ratios.
• The materials were successfully applied for targeted phosphorescence imaging of mitochondria due to redshifted absorption.

Conclusions:

• A new supramolecular strategy enables the construction of ultralong organic phosphorescent materials with unprecedented quantum yields.
• The developed supramolecular pins offer efficient redshifted phosphorescence in both solid-state and aqueous solutions.
• This work provides a promising pathway for advanced phosphorescent materials in imaging and optoelectronic applications.