Asymmetric Pt₁O₄-O_v Dual Active Sites Induced by NbO Clusters Promotes CO Synergistical Oxidation

Area of Science:

• Materials Science
• Catalysis
• Environmental Science

Background:

• Platinum single-atom catalysts on ceria (Pt/CeO2) show promise for CO oxidation.
• Poor low-temperature activity (<150 °C) is linked to symmetric Pt1O4 structures.

Purpose of the Study:

• To engineer a highly active and stable Pt1/CeO2 single-site catalyst for low-temperature CO oxidation.
• To investigate the role of asymmetric active sites and oxygen vacancies in enhancing catalytic performance.

Main Methods:

• Fabrication of asymmetric Pt1O4-oxygen vacancies (Ov) dual-active sites using NbO clusters.
• Characterization of catalyst structure and interactions (e.g., Ce-O-Nb).
• Evaluation of catalytic activity for CO oxidation and hydrocarbon pollutants.

Main Results:

• Achieved complete CO conversion at 150 °C with low Pt loading (0.1 wt%).
• NbO clusters induced asymmetric Pt1O4 sites and adjacent Ov, weakening Pt-O-Ce bonds.
• Synergistic effects between asymmetric Pt1O4 and Ov sites enhanced CO activation and O2 dissociation.

Conclusions:

• Asymmetric Pt1O4-Ov dual-active sites significantly boost low-temperature CO oxidation.
• This approach is effective for oxidizing other pollutants like toluene (C7H8) and propene (C3H6).
• Provides insights for designing efficient Pt-based catalysts for environmental applications.