Modulator-Induced Secondary Building Unit Control in Lanthanide-Porphyrin Metal-Organic Frameworks for Enhanced...

Area of Science:

• Materials Science
• Photochemistry
• Catalysis

Background:

• Metal-organic frameworks (MOFs) offer tunable properties for photocatalysis.
• Controlling secondary building units (SBUs) is key to optimizing MOF performance.
• Lanthanide-porphyrin frameworks (Ln-MOFs) show promise for singlet oxygen generation.

Purpose of the Study:

• To synthesize Ln-MOFs with diverse SBUs using a modulator-induced approach.
• To investigate the structure-property relationships between SBUs and photocatalytic activity.
• To enhance singlet oxygen generation and photocatalytic performance in Ln-MOFs.

Main Methods:

• Modulator-induced synthesis of lanthanide-porphyrin frameworks (QPF-3, QPF-4, QPF-5).
• Structural characterization of diverse SBUs (dinuclear cluster, 1D rod).
• Photocatalytic oxidation of 1,5-dihydroxynaphthalene to juglone using visible light.
• Spectroscopic and electrochemical analyses.

Main Results:

• Achieved diverse SBUs, including a 1D rod SBU in QPF-5(Yb).
• QPF-5(Yb) demonstrated the highest singlet oxygen (¹O₂) generation efficiency.
• QPF-5(Yb) showed a 6.1-fold increase in photocatalytic activity compared to QPF-4(Yb).
• Synergistic effects between Ln-SBUs and porphyrin ligands improved visible-light conversion and ¹O₂ generation.

Conclusions:

• Modulator selection is critical for controlling SBU formation and optimizing photocatalytic performance in Ln-porphyrin MOFs.
• The rod SBU in QPF-5(Yb) is crucial for its enhanced photocatalytic activity.
• These findings provide design principles for advanced photocatalysts for reactive oxygen species production and selective oxidation.