Dual-Function Metal-Organic Framework Membrane for High Proton Conduction and Photoswitch Sensor with a Large ON/OFF...

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Proton-conducting metal-organic framework (MOF) membranes offer potential for sensors.
• Controllable proton conduction is key for advanced applications.
• Existing materials lack dynamic and remote control mechanisms.

Purpose of the Study:

• To develop a photoacid-doped MOF membrane with light-controlled proton conductivity.
• To enhance proton conductivity and practicality by blending with SPES.
• To investigate the photoswitching behavior and ratio of the composite membrane.

Main Methods:

• Synthesized TCPP∈Im-UiO-66 using porphyrin (TCPP) and imidazole (im) ligands.
• Prepared photoacid-doped TCPP∈Im-UiO-66@PCN via photoacid impregnation.
• Fabricated hybrid membranes by blending TCPP∈Im-UiO-66@PCN with sulfonated poly(ether sulfone) (SPES).

Main Results:

• The composite membrane demonstrated light-responsive proton conductivity.
• Proton conductivity decreased from 0.12 S·cm⁻¹ (no light) to 0.017 S·cm⁻¹ (UV light).
• The optimal 5 wt% composite membrane achieved a maximum proton conductivity ON/OFF switching ratio of 7.1.

Conclusions:

• Developed a stable proton-conducting membrane integrated with photoacids.
• Offers a new strategy for proton exchange membranes in fuel cells.
• Provides a novel approach for remote photoproton sensing applications.