Role of the Support Oxidation State on the Catalytic Activity of Two- Dimensional Pt/TiOX Catalysts

The interaction between metal and support is known to substantially enhance catalytic activity. Herein, we investigate the effect of the support's oxidation state on the metal-support interaction (MSI) with twodimensional Pt/TiOx catalysts. Using titanium oxide supports with five different oxidation states and Pt nanoparticles deposited on the supports via arc plasma deposition, we accurately performed the CO oxidation reaction in a batch reactor. We confirmed that the catalyst whose support has the highest oxidation state exhibits the best catalytic activity. The catalysts' turnover frequency value varied sequentially from 4.0 to 19.4 at 513 K, and the activation energy also varied sequentially from 23.90 to 19.13 kcal/mol depending on the oxidation states of the supports. Kinetic studies have shown that the additional reaction pathway following the Mars-van Krevelen mechanism formed at the metal-oxide interface, which was affected by the oxidation states of the supports. The compositional effects of the support were confirmed by X-ray photoelectron spectroscopy analysis: the MSI effect was maintained even after the surface of the titanium oxides completely oxidized.

Automated summary

The interaction between metal and support significantly enhances catalytic activity. In this study, the effect of the support's oxidation state on the metal-support interaction (MSI) in two-dimensional Pt/TiOx catalysts was investigated. Pt nanoparticles were deposited on titanium oxide supports with five different oxidation states using arc plasma deposition, and CO oxidation reaction was accurately performed in a batch reactor. It was confirmed that the catalyst with the highest oxidation state of the support exhibited the best catalytic activity. The Mars-van Krevelen mechanism at the metal-oxide interface was affected by the oxidation states of the supports, and the compositional effects of the support were confirmed by X-ray photoelectron spectroscopy analysis.