Thermally Stable and Regenerable Platinum-Tin Clusters for Propane Dehydrogenation Prepared by Atom Trapping on Ceria

Haifeng Xiong; Sen Lin; Joris Goetze; Paul Pletcher; Hua Guo; Libor Kovarik; Kateryna Artyushkova; Bert M Weckhuysen; Abhaya K Datye

doi:10.1002/anie.201701115

Thermally Stable and Regenerable Platinum-Tin Clusters for Propane Dehydrogenation Prepared by Atom Trapping on Ceria

Angew Chem Int Ed Engl. 2017 Jul 24;56(31):8986-8991. doi: 10.1002/anie.201701115. Epub 2017 Jun 28.

Authors

Haifeng Xiong¹, Sen Lin², Joris Goetze³, Paul Pletcher³, Hua Guo⁴, Libor Kovarik⁵, Kateryna Artyushkova¹, Bert M Weckhuysen³, Abhaya K Datye¹

Affiliations

¹ Department of Chemical & Biological Engineering and Center for Microengineered Materials, University of New Mexico, Albuquerque, NM, 87131, USA.
² Research Institute of Photocatalysis, State Key Laboratory of Photocatalysis on Energy and Environment, Fuzhou University, Fuzhou, 350002, China.
³ Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands.
⁴ Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, NM, 87131, USA.
⁵ Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, 99352, USA.

Abstract

Ceria (CeO₂ ) supports are unique in their ability to trap ionic platinum (Pt), providing exceptional stability for isolated single atoms of Pt. The reactivity and stability of single-atom Pt species was explored for the industrially important light alkane dehydrogenation reaction. The single-atom Pt/CeO₂ catalysts are stable during propane dehydrogenation, but are not selective for propylene. DFT calculations show strong adsorption of the olefin produced, leading to further unwanted reactions. In contrast, when tin (Sn) is added to CeO₂ , the single-atom Pt catalyst undergoes an activation phase where it transforms into Pt-Sn clusters under reaction conditions. Formation of small Pt-Sn clusters allows the catalyst to achieve high selectivity towards propylene because of facile desorption of the product. The CeO₂ -supported Pt-Sn clusters are very stable, even during extended reaction at 680 °C. Coke formation is almost completely suppressed by adding water vapor to the feed. Furthermore, upon oxidation the Pt-Sn clusters readily revert to the atomically dispersed species on CeO₂ , making Pt-Sn/CeO₂ a fully regenerable catalyst.

Keywords: catalyst regeneration; ceria; light alkane dehydrogenation; single atoms; subnanometer Pt-Sn catalysis.

Publication types

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