AVS 63rd International Symposium & Exhibition
    Fundamental Discoveries in Heterogeneous Catalysis Focus Topic Thursday Sessions
       Session HC+SS-ThA

Paper HC+SS-ThA6
The Impact of Structure on the Catalytic Behavior of Cu2O Supported Pt Atoms

Thursday, November 10, 2016, 4:00 pm, Room 103A

Session: Advances in Theoretical Models and Simulations of Heterogeneously-catalyzed Reactions
Presenter: Andrew Therrien, Tufts University Department of Chemistry
Authors: A.J. Therrien, Tufts University Department of Chemistry
E.C.H. Sykes, Tufts University
Correspondent: Click to Email
Single site catalysts composed of individual atoms on various oxide supports have been a major research focus in recent years. Such catalysts exhibit novel reactivity with the benefit of 100% atom efficiency and a dramatic reduction in the precious metal loading. However, despite several experimental examples of efficient single atom catalysts, there is much debate regarding the structure and catalytic mechanisms of such catalysts and debate over whether single atoms or nanoparticles are the active species. Given the complexity of heterogeneous catalysts and the size scale of the active sites, there is a need for a surface science and microscopy approach to understand the structure and reactivity of atomically dispersed atoms on oxides.

We have studied the structure and reactivity of individual Pt atoms supported on oxidized Cu using scanning tunneling microscopy (STM) and temperature programmed reaction (TPR). We first elucidated the structure of the support, a previously observed but unsolved Cu2O overlayer on Cu, by density functional theory (DFT) and comparison of simulated STM images with experimental STM. We discovered that the oxide surface is inert towards CO oxidation, while the single Pt atom decorated surface is efficient for low-temperature CO oxidation. This system is also capable of water activation. Our combination of TPR and STM studies suggest that single Pt atoms supported on the oxide are indeed catalytically active and may be a good catalyst for the water-gas shift reaction.