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Title: Atomically Dispersed Pd–O Species on CeO 2(111) as Highly Active Sites for Low-Temperature CO Oxidation

Abstract

Ceria-supported Pd is a promising heterogeneous catalyst for CO oxidation relevant to environmental cleanup reactions. Pd loaded onto a nanorod form of ceria exposing predominantly (111) facets is already active at 50 °C. Here we report a combination of CO-FTIR spectroscopy and theoretical calculations that allows assigning different forms of Pd on the CeO 2(111) surface during reaction conditions. Single Pd atoms stabilized in the form of PdO and PdO 2 in a CO/O 2 atmosphere participate in a catalytic cycle involving very low activation barriers for CO oxidation. In conclusion, the presence of single Pd atoms on the Pd/CeO 2-nanorod, corroborated by aberration-corrected TEM and CO-FTIR spectroscopy, is considered pivotal to its high CO oxidation activity.

Authors:
 [1];  [1]; ORCiD logo [1];  [2];  [2];  [2];  [2]; ORCiD logo [1]
  1. Eindhoven Univ. of Technology, Eindhoven (The Netherlands)
  2. Univ. of New Mexico, Albuquerque, NM (United States)
Publication Date:
Research Org.:
The Netherlands Organization for Scientific Research (NWO) (The Netherlands)
Sponsoring Org.:
USDOE
OSTI Identifier:
1414915
Grant/Contract Number:
FG02-05ER15712
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
ACS Catalysis
Additional Journal Information:
Journal Volume: 7; Journal Issue: 10; Journal ID: ISSN 2155-5435
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; cerium oxide; CO oxidation; computational modeling; FTIR; mechanism; palladium; single site

Citation Formats

Spezzati, Giulia, Su, Yaqiong, Hofmann, Jan P., Benavidez, Angelica D., DeLaRiva, Andrew T., McCabe, Jay, Datye, Abhaya K., and Hensen, Emiel J. M. Atomically Dispersed Pd–O Species on CeO2(111) as Highly Active Sites for Low-Temperature CO Oxidation. United States: N. p., 2017. Web. doi:10.1021/acscatal.7b02001.
Spezzati, Giulia, Su, Yaqiong, Hofmann, Jan P., Benavidez, Angelica D., DeLaRiva, Andrew T., McCabe, Jay, Datye, Abhaya K., & Hensen, Emiel J. M. Atomically Dispersed Pd–O Species on CeO2(111) as Highly Active Sites for Low-Temperature CO Oxidation. United States. doi:10.1021/acscatal.7b02001.
Spezzati, Giulia, Su, Yaqiong, Hofmann, Jan P., Benavidez, Angelica D., DeLaRiva, Andrew T., McCabe, Jay, Datye, Abhaya K., and Hensen, Emiel J. M. 2017. "Atomically Dispersed Pd–O Species on CeO2(111) as Highly Active Sites for Low-Temperature CO Oxidation". United States. doi:10.1021/acscatal.7b02001. https://www.osti.gov/servlets/purl/1414915.
@article{osti_1414915,
title = {Atomically Dispersed Pd–O Species on CeO2(111) as Highly Active Sites for Low-Temperature CO Oxidation},
author = {Spezzati, Giulia and Su, Yaqiong and Hofmann, Jan P. and Benavidez, Angelica D. and DeLaRiva, Andrew T. and McCabe, Jay and Datye, Abhaya K. and Hensen, Emiel J. M.},
abstractNote = {Ceria-supported Pd is a promising heterogeneous catalyst for CO oxidation relevant to environmental cleanup reactions. Pd loaded onto a nanorod form of ceria exposing predominantly (111) facets is already active at 50 °C. Here we report a combination of CO-FTIR spectroscopy and theoretical calculations that allows assigning different forms of Pd on the CeO2(111) surface during reaction conditions. Single Pd atoms stabilized in the form of PdO and PdO2 in a CO/O2 atmosphere participate in a catalytic cycle involving very low activation barriers for CO oxidation. In conclusion, the presence of single Pd atoms on the Pd/CeO2-nanorod, corroborated by aberration-corrected TEM and CO-FTIR spectroscopy, is considered pivotal to its high CO oxidation activity.},
doi = {10.1021/acscatal.7b02001},
journal = {ACS Catalysis},
number = 10,
volume = 7,
place = {United States},
year = 2017,
month = 9
}

Journal Article:
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