• Corpus ID: 233004686

Fluxional Behavior at the Atomic Level and its Impact on Activity: CO Oxidation over CeO$_{2}$-supported Pt Catalysts

  title={Fluxional Behavior at the Atomic Level and its Impact on Activity: CO Oxidation over CeO\$\_\{2\}\$-supported Pt Catalysts},
  author={Joshua L Vincent and Peter A. Crozier},
Reducible oxides are widely used catalyst supports that can increase oxidation reaction rates by transferring their lattice oxygen at the metal-support interface. The interfacial oxidation process is typically described in terms of a Mars-van Krevelen mechanism. However, many outstanding questions remain unanswered regarding the atomic-scale structure and dynamic meta-stability (i.e., fluxional behavior) of the interface during catalysis. Here, we employ operando transmission electron… 
2 Citations

Figures from this paper

The role of surface spin polarization on ceria-supported Pt nanoparticles
In this work, we employ first-principles simulations to investigate the spin polarization of CeO2-(111) surface and its impact on interactions between a ceria support and Pt nanoparticles. For the
Direct detectors and their applications in electron microscopy for materials science
The past decade has seen rapid advances in direct detector technology for electron microscopy. Direct detectors are now having an impact on a number of techniques in transmission electron microscopy


Atomic-resolution Operando and Time-resolved In Situ TEM Imaging of Oxygen Transfer Reactions Catalyzed by CeO2-supported Pt Nanoparticles
Oxygen transfer is a critical functionality in automotive exhaust control and clean energy conversion. In these applications, catalytically active metal nanoparticles (e.g., Pt) are often dispersed
Structural changes in noble metal nanoparticles during CO oxidation and their impact on catalyst activity
Operando TEM studies of Pd NPs during CO oxidation are presented, which show reversible changes in both structure and activity with temperature, and it is proposed that adsorbed CO molecules suppress the activity of PD NPs at lower temperatures by stabilizing low index facets and reducing the number of active sites.
Visualization of oscillatory behaviour of Pt nanoparticles catalysing CO oxidation.
To successfully explain the oscillations of CO oxidation catalysed by Pt nanoparticles, the model must contain the phenomenon of refacetting, and the nanoreactor approach can provide atomic-scale information that is specific to surface sites, which will improve the understanding of dynamic properties in catalysis and related fields.
Dynamic structure of active sites in ceria-supported Pt catalysts for the water gas shift reaction
It is found that the perimeter Pt0 − O vacancy−Ce3+ sites are formed in the active structure, transformed at working temperatures and their appearance regulates the adsorbate behaviors and the dynamic nature of this site is a key mechanistic step for the WGS reaction.
Tuning Pt-CeO2 interactions by high-temperature vapor-phase synthesis for improved reducibility of lattice oxygen
It is elucidated that depositing single atoms via high temperature synthesis leads to improved reducibility of lattice oxygen on CeO2 yielding low temperature reactivity of Pt catalysts in CO oxidation.
Tuning the Structure of Platinum Particles on Ceria In Situ for Enhancing the Catalytic Performance of Exhaust Gas Catalysts.
A dynamic structural behavior of Pt nanoparticles on the ceria surface under reducing/oxidizing conditions was found at moderate temperatures (<500 °C) and exploited to enhance the catalytic activity
Control of Metal Nanocrystal Size Reveals Metal-Support Interface Role for Ceria Catalysts
Rate measurements are reported on samples in which the length of the ceria-metal interface was tailored by the use of monodisperse nickel, palladium, and platinum nanocrystals, and it is found that carbon monoxide oxidation inceria-based catalysts is greatly enhanced at the cia- metal interface sites for a range of group VIII metal catalysts.
Tuning the Pt/CeO2 Interface by in Situ Variation of the Pt Particle Size
Pt-CeO2-Al2O3 catalysts play an important role in diesel oxidation and three-way catalysis. In this study, the fast structural dynamics of both platinum and ceria in a 1 wt %Pt/5 wt %CeO2-Al2O3
Ensembles of Metastable States Govern Heterogeneous Catalysis on Dynamic Interfaces.
The catalytic interface should be viewed as an evolving statistical ensemble of many structures (rather than one structure), which flips the established paradigm and calls for a new theory, new modeling approaches, operando measurements, and updated design strategies.