Coordination-Defect-Driven Construction of Responsive Pure-MOF Microspheres for Switchable Mode-Dependent...

Area of Science:

• Materials Science
• Nanotechnology
• Optics

Background:

• Luminescent metal-organic frameworks (MOFs) show promise for information security but suffer from low-resolution identification due to spectral overlap.
• Existing MOF-based security systems require improvement in signal distinctiveness and encoding capacity.

Purpose of the Study:

• To develop a novel MOF-based security platform utilizing switchable whispering-gallery-mode (WGM) signals for enhanced anticounterfeiting.
• To create amorphous MOF microspheres capable of generating mode-dependent photonic barcodes.

Main Methods:

• Synthesized amorphous MOF microspheres using a chlorine coordination-defect-driven growth strategy.
• Investigated the whispering-gallery-mode (WGM) resonance and dimension-dependent characteristics of the microspheres.
• Demonstrated optical mode switching behavior induced by reversible framework shrinkage.

Main Results:

• Amorphous MOF microspheres exhibited well-defined circular morphology and typical WGM resonance.
• Successfully created dimension-dependent photonic barcodes with substantial encoding capacity.
• Achieved optical mode switching for covert photonic barcodes, enhancing information security.

Conclusions:

• Coordination-defect-induced amorphous MOF microspheres offer a novel mode-dependent security platform.
• The switchable WGM signals and photonic barcodes provide a robust strategy for information encryption and anticounterfeiting.
• This approach significantly enhances the security level compared to traditional broadband spectral signals.