Bimetallic Ag-Pt Sub-nanometer Supported Clusters as Highly Efficient and Robust Oxidation Catalysts

Fabio R Negreiros; Avik Halder; Chunrong Yin; Akansha Singh; Giovanni Barcaro; Luca Sementa; Eric C Tyo; Michael J Pellin; Stephan Bartling; Karl-Heinz Meiwes-Broer; Sönke Seifert; Prasenjit Sen; Sandeep Nigam; Chiranjib Majumder; Nobuyuki Fukui; Hisato Yasumatsu; Stefan Vajda; Alessandro Fortunelli

doi:10.1002/anie.201709784

Bimetallic Ag-Pt Sub-nanometer Supported Clusters as Highly Efficient and Robust Oxidation Catalysts

Angew Chem Int Ed Engl. 2018 Jan 26;57(5):1209-1213. doi: 10.1002/anie.201709784. Epub 2017 Dec 29.

Authors

Fabio R Negreiros¹, Avik Halder², Chunrong Yin², Akansha Singh³, Giovanni Barcaro¹, Luca Sementa¹, Eric C Tyo², Michael J Pellin², Stephan Bartling⁴, Karl-Heinz Meiwes-Broer⁴, Sönke Seifert⁵, Prasenjit Sen³, Sandeep Nigam⁶, Chiranjib Majumder⁶, Nobuyuki Fukui⁷, Hisato Yasumatsu⁸, Stefan Vajda^{2

9

10}, Alessandro Fortunelli^{1

11}

Affiliations

¹ CNR-ICCOM & IPCF, Consiglio Nazionale delle Ricerche, Pisa, Italy.
² Materials Science Division, Argonne National Laboratory, Lemont, IL, USA.
³ Harish-Chandra Research Institute, HBNI, Chhatnag Road, Jhunsi, Allahabad, 211019, India.
⁴ Institut für Physik, Universität Rostock, Rostock, Germany.
⁵ X-ray Science Division, Argonne National Laboratory, Lemont, IL, USA.
⁶ Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai-, 400 085, India.
⁷ East Tokyo Laboratory, Genesis Research Institute, Inc., Ichikawa, Chiba, 272-0001, Japan.
⁸ Cluster Research Laboratory, Toyota Technological Institute: in, East Tokyo Laboratory, Genesis Research Institute, Inc. Ichikawa, Chiba, 272-0001, Japan.
⁹ Nanoscience and Technology Division, Argonne National Laboratory, Lemont, IL, USA.
¹⁰ Institute for Molecular Engineering, University of Chicago, Chicago, IL, USA.
¹¹ Materials and Process Simulation Center, California Institute of Technology, Pasadena, CA, USA.

PMID: 29239093
DOI: 10.1002/anie.201709784

Abstract

A combined experimental and theoretical investigation of Ag-Pt sub-nanometer clusters as heterogeneous catalysts in the CO→CO₂ reaction (COox) is presented. Ag₉ Pt₂ and Ag₉ Pt₃ clusters are size-selected in the gas phase, deposited on an ultrathin amorphous alumina support, and tested as catalysts experimentally under realistic conditions and by first-principles simulations at realistic coverage. In situ GISAXS/TPRx demonstrates that the clusters do not sinter or deactivate even after prolonged exposure to reactants at high temperature, and present comparable, extremely high COox catalytic efficiency. Such high activity and stability are ascribed to a synergic role of Ag and Pt in ultranano-aggregates, in which Pt anchors the clusters to the support and binds and activates two CO molecules, while Ag binds and activates O₂ , and Ag/Pt surface proximity disfavors poisoning by CO or oxidized species.

Keywords: ab initio calculations; alloys; reaction mechanisms; supported catalysts; ultrathin oxide films.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.