Fluorine-Mediated Engineering of Stable High-Valence Single-Atom Catalysts

Area of Science:

• Materials Science
• Catalysis
• Electrochemistry

Background:

• High-valence single-atom catalysts (HVSACs) offer superior activity due to efficient electron transfer.
• However, HVSACs are thermodynamically unstable and prone to aggregation, limiting their practical application.
• Developing stable HVSACs is crucial for advanced catalytic and energy storage systems.

Purpose of the Study:

• To develop a universal and stable synthesis method for HVSACs.
• To investigate the structural and electronic properties of fluorine-coordinated HVSACs.
• To demonstrate the enhanced catalytic performance and durability of these novel catalysts.

Main Methods:

• Incorporation of high-electronegativity fluorine (F) atoms to coordinate with metal atoms (M) on nitrogen-carbon supports.
• Formation of an asymmetric planar M-N2F2 structure.
• Synthesis and characterization of HVSACs for 22 different metal elements.

Main Results:

• A universal approach to synthesize stable HVSACs was successfully demonstrated.
• The M-N2F2 structure stabilizes high-valence metal centers and enhances spin polarization.
• The synthesized fluorine-modified HVSACs showed high activity and durability in oxygen reduction reactions and zinc-air batteries.
• This method was validated for 22 individual metal elements.

Conclusions:

• Fluorine coordination provides a robust strategy for stabilizing HVSACs.
• The asymmetric M-N2F2 motif is a promising design for next-generation catalysts.
• This work opens new avenues for designing stable and highly active single-atom catalysts for various applications.