Tunable fluorescence emission based on multi-layered MOF-on-MOF

Area of Science:

• Materials Science
• Nanotechnology
• Photochemistry

Background:

• Luminescent metal-organic frameworks (MOFs) are crucial for advanced optical applications.
• Tuning MOF luminescence, especially to achieve white light, remains a significant challenge.
• Existing methods often lack precise control over emission properties.

Purpose of the Study:

• To develop a flexible hierarchical confinement strategy for tuning MOF luminescence.
• To achieve tunable emission from blue to red, including white light, using MOF-on-MOF structures.
• To demonstrate the efficacy of this strategy for controlling dye encapsulation and emission characteristics.

Main Methods:

• Hierarchical confinement strategy using MOF-on-MOF architecture.
• In situ encapsulation and seed-mediated synthesis of ZIF-8@dye@ZIF-8@dye.
• Tuning dye concentration and inner/outer layer structures for emission control.
• Investigation of luminescence in both dispersed and solid states.

Main Results:

• Successfully synthesized ZIF-8@dye@ZIF-8@dye materials with tunable luminescence.
• Achieved white light emission in dispersed state with ZIF-8@0.125perylene@ZIF-8@25RhB.
• Demonstrated white light emission in solid state with ZIF-8@perylene@ZIF-8@3RhB.
• Confirmed the necessity of the hierarchical confinement strategy for white light regulation, unlike simple mixtures.

Conclusions:

• The MOF-on-MOF hierarchical confinement strategy offers a flexible approach to tune luminescence emission.
• This method enables precise control over dye arrangement, facilitating the realization of white light emission.
• The strategy holds potential for developing other functional optical MOF materials.