Symmetry Evolution Induced 2D Pt Single Atom Catalyst with High Density for Alkaline Hydrogen Oxidation

Area of Science:

• Materials Science
• Catalysis
• Electrochemistry

Background:

• Single-atom catalyst performance is dictated by the surrounding chemical environment.
• Zeolitic imidazolate frameworks-8 (ZIF-8) possess a tetrahedral coordination structure.

Purpose of the Study:

• To develop a novel 2D single-atom catalyst (SAC) with a planar square coordination structure.
• To enhance the catalytic activity for the hydrogen oxidation reaction (HOR).

Main Methods:

• A salt-assisted method was used to transform ZIF-8's coordination structure.
• Carbonization and electrodeposition were employed to create 2D-Pt SAC.
• Characterization of Pt loading and coordination symmetry.

Main Results:

• A planar square coordination structure was successfully synthesized, creating additional defect sites on 2D nitrogen and carbon (NC) carriers.
• The 2D-Pt SAC exhibited higher Pt loading (0.49 µg cm⁻²) compared to 3D-Pt SAC (0.37 µg cm⁻²).
• The 2D-Pt SAC demonstrated superior mass activity (2396 A gPt⁻¹) for HOR catalysis, significantly exceeding commercial Pt/C and 3D-Pt SAC.

Conclusions:

• The developed 2D-Pt SAC with planar square coordination shows exceptional promise for electrocatalysis.
• This approach offers a new pathway for designing high-performance single-atom catalysts.
• The enhanced activity is attributed to the unique 2D structure and defect sites.