Anisotropic Excitation-Modulated Multi-Color Three-photon Excited Luminescence in Ln-MOF Heterostructure

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Multi-photon excited luminescence (MPEL) is crucial for optoelectronics, offering multi-color emission and optical anisotropy.
• Challenges exist in integrating and orienting diverse MPEL units for advanced functionalities.

Purpose of the Study:

• To develop a novel heterostructure for highly-integrated and orientedly-assembled MPEL units.
• To achieve multi-dimensional MPEL modulation using a single pump source.

Main Methods:

• A hierarchical assembly-in situ doping strategy was employed to create a lanthanide-graded metal-organic framework (MOF) heterostructure.
• Lanthanide ions (Ln3+) and specifically designed ligands were utilized as energy acceptor and donor units, respectively.

Main Results:

• The resulting triblock heterostructure demonstrated multi-dimensional three-photon excited luminescence (3PEL) modulation, with switchable emission bands and intensities.
• Achieved a record-high MPEL color gamut (>30% sRGB) and high linear polarization (up to 88.6%) in MOFs.
• Precise integration and orientation of photonic units enabled anisotropic 3PEL modulation.

Conclusions:

• The developed MOF-based heterostructure offers significant advancements in MPEL modulation capabilities.
• The findings pave the way for on-demand functional up-conversion luminescent materials for photonic modulation.
• Potential applications include nonlinear optical switches, logic gates, and optical barcodes.