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Title: Giant onsite electronic entropy enhances the performance of ceria for water splitting

Previous studies have shown that a large solid-state entropy of reduction increases the thermodynamic efficiency of metal oxides, such as ceria, for two-step thermochemical water splitting cycles. In this context, the configurational entropy arising from oxygen off-stoichiometry in the oxide, has been the focus of most previous work. Here we report a different source of entropy, the onsite electronic configurational entropy, arising from coupling between orbital and spin angular momenta in lanthanide f orbitals. We find that onsite electronic configurational entropy is sizable in all lanthanides, and reaches a maximum value of ≈4.7 k B per oxygen vacancy for Ce 4+/Ce 3+ reduction. This unique and large positive entropy source in ceria explains its excellent performance for high-temperature catalytic redox reactions such as water splitting. Our calculations also show that terbium dioxide has a high electronic entropy and thus could also be a potential candidate for solar thermochemical reactions.
Authors:
 [1] ; ORCiD logo [1] ; ORCiD logo [2] ; ORCiD logo [3] ;  [4] ;  [1]
  1. Northwestern Univ., Evanston, IL (United States). Department of Materials Science and Engineering
  2. Technical University of Denmark (Denmark). Department of Energy Conversion and Storage
  3. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  4. Yale Univ., New Haven, CT (United States). Department of Applied Physics; Yale Energy Sciences Institute, West Haven, CT (United States)
Publication Date:
Grant/Contract Number:
AC52-07NA27344; FG02-07ER46433
Type:
Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal Issue: 1; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Research Org:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Computational methods; Electronic structure; Energy modelling
OSTI Identifier:
1395468

Naghavi, S. Shahab, Emery, Antoine A., Hansen, Heine A., Zhou, Fei, Ozolins, Vidvuds, and Wolverton, Chris. Giant onsite electronic entropy enhances the performance of ceria for water splitting. United States: N. p., Web. doi:10.1038/s41467-017-00381-2.
Naghavi, S. Shahab, Emery, Antoine A., Hansen, Heine A., Zhou, Fei, Ozolins, Vidvuds, & Wolverton, Chris. Giant onsite electronic entropy enhances the performance of ceria for water splitting. United States. doi:10.1038/s41467-017-00381-2.
Naghavi, S. Shahab, Emery, Antoine A., Hansen, Heine A., Zhou, Fei, Ozolins, Vidvuds, and Wolverton, Chris. 2017. "Giant onsite electronic entropy enhances the performance of ceria for water splitting". United States. doi:10.1038/s41467-017-00381-2. https://www.osti.gov/servlets/purl/1395468.
@article{osti_1395468,
title = {Giant onsite electronic entropy enhances the performance of ceria for water splitting},
author = {Naghavi, S. Shahab and Emery, Antoine A. and Hansen, Heine A. and Zhou, Fei and Ozolins, Vidvuds and Wolverton, Chris},
abstractNote = {Previous studies have shown that a large solid-state entropy of reduction increases the thermodynamic efficiency of metal oxides, such as ceria, for two-step thermochemical water splitting cycles. In this context, the configurational entropy arising from oxygen off-stoichiometry in the oxide, has been the focus of most previous work. Here we report a different source of entropy, the onsite electronic configurational entropy, arising from coupling between orbital and spin angular momenta in lanthanide f orbitals. We find that onsite electronic configurational entropy is sizable in all lanthanides, and reaches a maximum value of ≈4.7 kB per oxygen vacancy for Ce4+/Ce3+ reduction. This unique and large positive entropy source in ceria explains its excellent performance for high-temperature catalytic redox reactions such as water splitting. Our calculations also show that terbium dioxide has a high electronic entropy and thus could also be a potential candidate for solar thermochemical reactions.},
doi = {10.1038/s41467-017-00381-2},
journal = {Nature Communications},
number = 1,
volume = 8,
place = {United States},
year = {2017},
month = {8}
}

Works referenced in this record:

Generalized Gradient Approximation Made Simple
journal, October 1996
  • Perdew, John P.; Burke, Kieron; Ernzerhof, Matthias
  • Physical Review Letters, Vol. 77, Issue 18, p. 3865-3868
  • DOI: 10.1103/PhysRevLett.77.3865

Projector augmented-wave method
journal, December 1994

Materials for fuel-cell technologies
journal, November 2001
  • Steele, Brian C. H.; Heinzel, Angelika
  • Nature, Vol. 414, Issue 6861, p. 345-352
  • DOI: 10.1038/35104620

From ultrasoft pseudopotentials to the projector augmented-wave method
journal, January 1999

A thermodynamic study of nonstoichiometric cerium dioxide
journal, November 1975
  • Panlener, R. J.; Blumenthal, R. N.; Garnier, J. E.
  • Journal of Physics and Chemistry of Solids, Vol. 36, Issue 11, p. 1213-1222
  • DOI: 10.1016/0022-3697(75)90192-4

Materials-Related Aspects of Thermochemical Water and Carbon Dioxide Splitting: A Review
journal, October 2012
  • Roeb, Martin; Neises, Martina; Monnerie, Nathalie
  • Materials, Vol. 5, Issue 11, p. 2015-2054
  • DOI: 10.3390/ma5112015