Self-assembled porous polymer films for improved oxygen sensing

Area of Science:

• Materials Science
• Chemical Sensors
• Biomedical Engineering

Background:

• Phosphorescence-based oxygen sensors are crucial for biological monitoring.
• Developing high-performance sensors requires advanced fabrication techniques.
• Common polymers often lack the desired sensing characteristics.

Purpose of the Study:

• To create high-performance phosphorescent oxygen sensing films using simple fabrication methods.
• To investigate the impact of induced porosity on oxygen sensing properties.
• To correlate porous film morphology with enhanced sensing performance.

Main Methods:

• Utilized evaporation-based phase separation and breath figure techniques to create porous polymer films.
• Fabricated films with pore sizes ranging from 37 nm to 141 µm and up to 74% porosity.
• Evaluated oxygen sensing properties using an optoelectronic setup in transmission and reflection configurations.

Main Results:

• Porous films demonstrated a 7.9-fold increase in dynamic range and a 7.3-fold increase in maximum sensitivity compared to non-porous films.
• Achieved improved linearity with a half-sensitivity point at 43% O2 (V/V).
• High porosity films exhibited an order of magnitude reduction in recovery time and were humidity-independent.

Conclusions:

• Simple fabrication techniques can significantly enhance the oxygen sensing performance of common polymers.
• Induced porosity in phosphorescent films is directly related to improved sensing capabilities.
• The developed porous films offer a promising platform for advanced oxygen monitoring in biological environments.