Record-large indium-oxo clusters: synthesis, hierarchical assembly, and efficient optical limiting.

Area of Science:

• Materials Science
• Inorganic Chemistry
• Nanotechnology

Background:

• High-nuclearity indium-oxo clusters (InOCs) are crucial for modeling indium oxide (In2O3) nanoparticles.
• The synthesis of these complex clusters presents significant challenges.

Purpose of the Study:

• To develop a novel synthetic strategy for accessing large, discrete indium-oxo clusters.
• To explore the functionalization and assembly of these clusters into advanced materials.
• To evaluate the optical limiting properties of the synthesized indium-oxo clusters.

Main Methods:

• Employed a dual-ligand strategy for the rational synthesis of bixbyite-type In15-oxo clusters.
• Utilized carboxylate lability for facile functionalization, yielding InOC-38, InOC-39, and InOC-40.
• Applied cluster-docking and hierarchical assembly strategies to create dimers (InOC-41) and chains (InOC-42).

Main Results:

• Synthesized the largest discrete indium-oxo cores reported to date (In15).
• Achieved record optical limiting performance with InOC-38 and InOC-41, surpassing existing cluster-based materials.
• Demonstrated the processability of these materials into flexible, transparent films for optical applications.

Conclusions:

• The dual-ligand strategy provides a robust method for synthesizing high-nuclearity InOCs.
• The developed InOCs exhibit superior optical limiting capabilities, driven by their unique architectures and π-conjugated ligands.
• These findings highlight the potential of InOCs in practical optical limiting devices.