Fluorescence Modulation in UiO-66-NH2 via Photooxidation and Selective Reduction
Yongdeok Ahn1,2, Minsoo Park1, Younghu Son3
1Department of Physics and Chemistry, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Republic of Korea.
ACS Omega
|September 29, 2025
Summary
Metal-organic frameworks (MOFs) show tunable fluorescence. Photo-oxidation quenches fluorescence, but mild alcohols restore it, enhancing porosity and enabling reconfigurable optical materials.
Area of Science:
- Materials Science
- Chemistry
- Nanotechnology
Background:
- Emissive metal-organic frameworks (MOFs) possess tunable photophysical properties.
- These properties are sensitive to coordination environment and structural configuration.
Purpose of the Study:
- To demonstrate fluorescence modulation in UiO-66-NH2 via photo-oxidation and solvent-mediated recovery.
- To establish a structure-function relationship governed by localized redox chemistry in MOFs.
Main Methods:
- Visible-light irradiation to induce photo-oxidation and reactive oxygen species formation.
- Treatment with various alcohols for solvent-mediated reduction and recovery.
- Nitrogen adsorption analysis to assess porosity changes.
Main Results:
- Photo-oxidation led to ligand and metal-oxo cluster oxidation, causing fluorescence loss.
- Mild alcohol treatment selectively removed oxidative species, partially restoring fluorescence and porosity.
- Nitrogen uptake increased in some alcohol-treated samples, indicating pore expansion.
Conclusions:
- Localized redox chemistry dictates MOF structure-function relationships.
- UiO-66-NH2 can be reconfigured optically and texturally through redox stimuli.
- This work provides a platform for designing switchable photophysical and porous materials.
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