Research Summary

• Pt/rutile catalyst exhibits significantly higher low-temperature CO oxidation activity and a lower activation energy compared to Pt/anatase. 

• CO-TPD and DRIFTS analyses reveal that morphological changes during the reaction lead to a weaker interaction between CO and the Pt surface on the rutile support. 

• In situ studies demonstrate that CO adsorbed on the terrace sites of Pt clusters on rutile reacts exceptionally fast with oxygen, which is the primary origin of its superior catalytic activity. 

Journal of Physical Chemistry C. 2023, 127, 15, 7142-7150 

• The specific CO oxidation activity of Pt/rutile catalysts strongly increases with higher Pt dispersion, whereas Pt/anatase catalysts remain structure-insensitive regardless of Pt loading. 

• Sub-nm Pt clusters on rutile maintain a stable positive reaction order for CO, while identical clusters on anatase sinter into 1–2 nm particles and shift to a zeroth reaction order during the reaction. 

• The superior stability of 2D raft-like Pt clusters on the rutile support prevents sintering, yielding an exceptionally low activation energy (17 kJ/mol) and enhanced catalytic performance. 

Journal of Physical Chemistry C. 2025, 129 (28), 12827-12835 

• Sulfur tolerance of Pt/TiO2 was linearly depended on the surface area of TiO2. 

• CO oxidation with H2O improved sulfur tolerance than CO oxidation without H2O.

• Pt surfaces were sustained for CO oxidation from sulfur poisoning due to H2O.

Chemical Engineering Journal 2026, 527, 171876