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Insight of the stability and activity of platinum single atoms on ceria

  • Xuxu Ye
  • Hengwei Wang
  • Yue Lin
  • Xinyu Liu
  • Lina Cao
  • Jian Gu
  • Junling LuEmail author
Research Article
  • 64 Downloads

Abstract

Single-atom catalysts (SACs) have recently attracted broad attention in the catalysis field due to their maximized atom efficiency and unique catalytic properties. An atomic-level understanding of the interaction between the metal atoms and support is vital for developing stable and high-performance SACs. In this work, Pt1 single atoms with loadings up to 4 wt.% were fabricated on ceria nanorods using the atomic layer deposition technique. To understand the Pt–O–Ce bond interfacial interactions, the stability of Pt1 single atoms in the hydrogen reducing environment was extensively investigated by using in situ diffuse reflectance infrared Fourier transform spectroscopy CO chemisorption measurements. It was found that ceria defect sites, metal loadings and high-temperature calcination are effective ways to tune the stability of Pt1 single atoms in the hydrogen environment. X-ray photoemission spectroscopy further showed that Pt1 single atoms on ceria are dominantly at a +2 valence state at the defect and step edge sites, while those on terrace sites are at a +4 state. The above tailored stability and electronic properties of Pt1 single atoms are found to be strongly correlated with the catalytic activity in the dry and water-mediated CO oxidation reactions.

Keywords

single atom catalyst Pt1/CeO2 metal–support interaction stability water-mediated CO oxidation 

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Notes

Acknowledgements

This work was supported by the National Natural Science Foundation of China (Nos. 21673215 and 21473169), the Fundamental Research Funds for the Central Universities (No. WK2060030029), and the Max-Planck Partner Group, Hefei Science Center, CAS, Users with Potential. The authors also gratefully thank the BL10B beamlines at National Synchrotron Radiation Laboratory (NSRL), China.

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© Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Xuxu Ye
    • 1
  • Hengwei Wang
    • 1
  • Yue Lin
    • 2
  • Xinyu Liu
    • 1
  • Lina Cao
    • 1
  • Jian Gu
    • 1
  • Junling Lu
    • 1
    • 2
    Email author
  1. 1.Department of Chemical Physics, iChEM, CAS Key Laboratory of Materials for Energy ConversionUniversity of Science and Technology of ChinaHefeiChina
  2. 2.Hefei National Laboratory for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefeiChina

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