(521di) Modulation of 0D-2D Hybrids for Improved Efficiency of Pt on Ultra-Thin TiO2 Support

The catalytic properties of the supported nanoparticles are widely studied. The interface between the substrate and NPs plays an important role in determining the catalytic pathway. Recent studies have shown that the “active” sites participating in catalysis reactions such as Pt NPs in water‐gas shift reactions are on the interface of the support and NP. While there are multiple studies focused on the identification of appropriate support, much less emphasis has been given towards the tunability of the support-nanoparticle interface.

A novel approach of Catalytic condenser allows dynamic changes in the electronic state of the catalyst, resulting in charge accumulation and depletion at the active sites, forcing the reaction pathway in a specific direction.[1] The charge density in these nanoparticles can be altered based on the support used for these nanoparticles. Such an approach presents the potential to improve the NP catalytic performance beyond the Sabatier optimum.

We utilized a model Pt NP-TiO2 ultra-thin films a model 0D-2D hybrid nanocatalyst system for systematically studying their interfacial dynamics and tuning the active sites of Pt nanoparticles using this architecture. The atomic layer deposition of the ultrathin TiO2 layer allows the deposition of 2D-like continuous TiO2 support layers on various surfaces which can then be further functionalized by controlled deposition of Pt nanoparticles. We leverage this hybrid system for conducting a correlative study of the catalysis using a wide range of in-situ and ex-situ characterization techniques such as low-energy electron microscopy (LEEM) and ambient pressure X-ray photoelectron spectroscopy (APXPS) with water-gas shift reaction activity studies elucidating the role of “active” sites.

[1] Onn, T. M., Gathmann, S. R., Guo, S., Solanki, S. P. S., Walton, A., Page, B. J., ... & Dauenhauer, P. J. ﴾2022﴿. Platinum Graphene Catalytic Condenser for Millisecond Programmable Metal Surfaces. Journal of the American Chemical Society, 144﴾48﴿, 22113‐22127.