Highly sensitive switching of solid-state luminescence by controlling intersystem crossing

Area of Science:

• Materials Science
• Organic Chemistry
• Photophysics

Background:

• Intelligent materials with mechanoresponsive luminescence (MRL) are highly desirable but challenging to develop.
• Existing MRL materials often lack high sensitivity, contrast, or reversibility.

Purpose of the Study:

• To design and synthesize high-performance On-Off MRL materials.
• To investigate a novel strategy for controlling mechanoresponsive luminescence through molecular design.

Main Methods:

• Incorporation of nitrophenyl groups into aggregation-induced emission (AIE) luminogen cores.
• Utilizing the control of intersystem crossing (ISC) for On-Off luminescence switching.
• Experimental and theoretical investigations (e.g., computational studies) to understand the mechanism.

Main Results:

• Successfully developed On-Off MRL materials with high sensitivity and contrast.
• The nitrophenyl group was found to effectively open a non-radiative ISC channel, enabling the On-Off behavior.
• The twisted AIE core provided enhanced reversibility and reduced switching pressure.

Conclusions:

• A new design strategy for high-performance On-Off MRL materials based on AIE luminogens and nitrophenyl groups has been established.
• The developed materials demonstrate potential for applications in optical information recording and haptic sensing.
• This work significantly advances the field of mechanoresponsive luminescence materials.