Zirconium Carbide Clusters Stabilized within Carbon Cages

Area of Science:

• Fullerene Chemistry
• Materials Science
• Nanotechnology

Background:

• Zirconium-based endohedral metallofullerenes (EMFs) have been detected in gas phase since 1992.
• Bulk synthesis of Zr-based EMFs has remained elusive for over three decades, hindering further research and application.

Purpose of the Study:

• To achieve the first successful bulk synthesis of zirconium-based endohedral metallofullerenes (EMFs).
• To characterize the structure and electronic properties of newly synthesized Zr-based carbide clusterfullerenes.
• To provide insights into EMF formation mechanisms and guide future encapsulation strategies.

Main Methods:

• Optimized synthesis strategy using zirconium carbide as the metal source.
• Isolation and characterization of three Zr-based carbide clusterfullerenes: Zr2C2@C78, Zr2C2@C80, and Zr3C2@C80.
• Single-crystal X-ray diffraction for structural determination.
• Combined experimental and theoretical studies for electronic structure analysis.

Main Results:

• Successful synthesis of three Zr-based carbide clusterfullerenes: Zr2C2@D3h(5)-C78, Zr2C2@Ih(7)-C80, and Zr3C2@Ih(7)-C80.
• Structural analysis revealed a planar rhombic Zr2C2 cluster and a trifoliate Zr3C2 cluster with unique coordination modes.
• Electronic structures were determined as (Zr2C2)6+@(C2n)6- and (Zr3C2)6+@(Ih(7)-C80)6-.

Conclusions:

• This study presents the first successful bulk synthesis of Zr-based EMFs, resolving a long-standing challenge in fullerene chemistry.
• The unique structures and electronic properties of these Zr-based EMFs offer new insights into arc-discharge reactions and EMF formation.
• The findings provide a foundational guideline for encapsulating new elements into fullerene cages, paving the way for novel EMF design.