Temperature-Induced Structure Reconstruction to Prepare a Thermally Stable Single-Atom Platinum Catalyst

Area of Science:

• Materials Science
• Catalysis
• Nanotechnology

Background:

• Single-atom catalysts (SACs) face challenges with atom migration and agglomeration at high temperatures due to high surface free energy.
• Support restructuring offers a potential strategy to anchor single atoms, improving their stability in demanding thermal environments.

Purpose of the Study:

• To develop a highly stable single-atom platinum (Pt) catalyst for high-temperature applications.
• To investigate the role of support restructuring in anchoring single-atom Pt species.
• To optimize catalyst performance for high-temperature methane oxidation.

Main Methods:

• Utilized manganese oxide (Mn3O4) as a restructurable support for single-atom Pt loading.
• Employed high-temperature treatment to transform the support into Mn2O3, anchoring Pt atoms.
• Applied hydrogen peroxide (H2O2) etching to optimize catalyst structure and Pt dispersion.

Main Results:

• Achieved exceptional thermal stability for single-atom Pt on Mn2O3, withstanding 800°C for 5 days in humid air.
• Identified high-valence Pt4+ species with strong covalent bonds to Mn2O3 as crucial for anchoring isolated Pt atoms.
• The optimized catalyst demonstrated superior performance in high-temperature methane oxidation due to enhanced Pt exposure and Pt-Mn2O3 interaction.

Conclusions:

• Temperature-induced support reconstruction is an effective strategy for stabilizing single-atom catalysts.
• The single-atom Pt-on-Mn2O3 catalyst exhibits remarkable thermal stability and catalytic activity for methane oxidation.
• Strong interaction between Pt atoms and the restructured support is key to preventing agglomeration and maintaining performance.