Hypsochromically-shifted Emission of Metal-organic Frameworks Generated through Post-synthetic Ligand Reduction

Luminescent materials with tunable emission are becoming increasingly desirable as we move towards needing efficient Light Emitting Diodes (LEDs) for displays. Key to developing better displays is the advancement of strategies for rationally designing emissive materials that are tunable and efficient. We report a series of emissive metal-organic frameworks (MOFs) generated using BUT-10 (BUT: Beijing University of Technology) that emits green light with lambda(max) at 525 nm. Post-synthetic reduction of the ketone on the fluorenone ligand in BUT-10 generates new materials, BUT-10-M and BUT-10-R. The emission for BUT-10-R is hypsochromically-shifted by 113 nm. Multivariate BUT-10-M structures demonstrate emission with two maxima corresponding to the emission of both fluorenol and fluorenone moieties present in their structures. Our study represents a novel post-synthetic ligand reduction strategy for producing emissive MOFs with tunable emission ranging from green, white-blue to deep blue.

Automated summary

Tunable and efficient luminescent materials are needed for the development of better displays. This study presents a novel post-synthetic ligand reduction strategy to produce emissive metal-organic frameworks (MOFs) with tunable emission ranging from green to deep blue. The emission of these MOFs can be modified by reducing the ketone on the fluorenone ligand. The findings offer potential for the design of more efficient light emitting diodes (LEDs) for displays.