Ultra-Linear Afterglow Oxygen Sensing and Visualization in Morphology-Engineered Phosphorescent Microporous...

Area of Science:

• Materials Science
• Chemical Sensing
• Photophysics

Background:

• Phosphorescence-based oxygen sensors are valuable for oxygen visualization but suffer from nonlinear responses and low sensitivity due to heterogeneous environments.
• Physically mixed systems often lead to phosphor aggregation, limiting sensor performance.

Purpose of the Study:

• To develop a scalable strategy for constructing microporous films with room-temperature phosphorescence (RTP) for ultralinear oxygen sensing.
• To overcome the limitations of nonlinear Stern-Volmer responses and low sensitivity in existing oxygen sensors.

Main Methods:

• Covalently integrating triphenylamine-derived phosphors into amphiphilic copolymers to suppress aggregation.
• Utilizing volatile nonazeotropic and azeotropic mixed solvents to direct the formation of interconnected microporous networks or perforated microcells.
• Characterizing the phosphorescent films for their RTP lifetimes, oxygen sensing linearity, and reproducibility.

Main Results:

• Constructed microporous films with RTP exhibiting ultralinear oxygen sensing (R² > 0.999).
• Achieved high Stern-Volmer quenching constants (Ksv up to 2071) and long RTP lifetimes (∼100 ms).
• Demonstrated excellent reproducibility and potential for real-time visualization of gas flow and underwater dissolved oxygen.

Conclusions:

• The morphological-engineering strategy enables the creation of high-performance, ultralinear oxygen sensors.
• These RTP-based microporous films offer a reliable platform for advanced oxygen monitoring applications.
• The approach effectively suppresses phosphor aggregation and enhances the quenchable phosphorescent fraction.