Bridged Stilbenes: AIEgens Designed via a Simple Strategy to Control the Non-radiative Decay Pathway

Area of Science:

• Materials Science
• Organic Chemistry
• Photophysics

Background:

• Aggregation-induced emission (AIE) luminogens (AIEgens) are crucial for solid-state applications, requiring high fluorescence quantum yield.
• Understanding the mechanism of AIE, particularly the role of steric effects in preventing non-radiative decay, is key to designing efficient AIEgens.

Purpose of the Study:

• To design and investigate novel small-molecular dyes exhibiting AIE properties.
• To explore the relationship between molecular structure, steric hindrance, and AIE behavior in bridged stilbenes.
• To develop high-performance AIEgens for expanded applications.

Main Methods:

• Theoretical investigation of non-radiative decay pathways in a series of bridged stilbenes.
• Synthesis of bridged stilbenes with varying alkyl chain lengths.
• Characterization of photophysical properties in both solution and solid states.

Main Results:

• Bridged stilbenes with short alkyl chains showed strong fluorescence in solution and solid states.
• Bridged stilbenes with long alkyl chains exhibited significant aggregation-induced emission (AIE).
• The developed bridged stilbenes, BPST[7] and DPB[7], demonstrated excellent AIE behavior, validating theoretical predictions.

Conclusions:

• Molecular design based on steric effects is an effective strategy for achieving AIE.
• The developed bridged stilbenes are promising candidates for advanced AIE applications.
• This study provides insights into the rational design of novel AIE luminogens.