Enthalpy of formation of yttria-doped ceria

Weiqun Chen; Theresa A. Lee; Alexandra Navrotsky

doi:10.1557/JMR.2005.0017

Enthalpy of formation of yttria-doped ceria

Weiqun Chen, Theresa A. Lee, Alexandra Navrotsky

Research output: Contribution to journal › Article › peer-review

32 Scopus citations

Abstract

Solid solutions (1 - x)CeO₂ - xYO_1.5 (0 ≤ × ≤ 0.36) were prepared by coprecipitation and sol-gel methods. Their enthalpy of formation relative to the end-members, fluorite-type cubic CeO₂ and C-type YO_1.5 was determined by oxide melt solution calorimetry. The enthalpy of drop solution shows a roughly linear trend with composition. Extrapolation to x = 1 gives the transition enthalpy of C-type to cubic fluorite YO_1.5 as 22.2 ± 6.7 kJ/mol. This linear behavior is in contrast to the strong curvature seen in the ZrO₂ - YO_1.5 and HfO₂ - YO_1.5 systems. The slightly positive enthalpy of formation of CeO₂ - YO_1.5 is strikingly different from the strongly negative enthalpies of formation of ZrO₂ - YO_1.5 and HfO₂ - YO_1.5. The thermodynamics of CeO₂ - YO_1.5 is analyzed in terms of defect association and oxygen vacancy distribution. Specifically, the association of oxygen vacancies with the tetravalent cations in the zirconia and hafnia systems, in contrast to the preference of vacancies for nearest neighbor yttrium sites in the ceria systems, may explain the different energetics.

Original language	English (US)
Pages (from-to)	144-150
Number of pages	7
Journal	Journal of Materials Research
Volume	20
Issue number	1
DOIs	https://doi.org/10.1557/JMR.2005.0017
State	Published - Jan 2005
Externally published	Yes

ASJC Scopus subject areas

General Materials Science
Condensed Matter Physics
Mechanics of Materials
Mechanical Engineering

Access to Document

10.1557/JMR.2005.0017

Cite this

@article{0d90c819b520401e91ae5740ca7695eb,

title = "Enthalpy of formation of yttria-doped ceria",

abstract = "Solid solutions (1 - x)CeO2 - xYO1.5 (0 ≤ × ≤ 0.36) were prepared by coprecipitation and sol-gel methods. Their enthalpy of formation relative to the end-members, fluorite-type cubic CeO2 and C-type YO1.5 was determined by oxide melt solution calorimetry. The enthalpy of drop solution shows a roughly linear trend with composition. Extrapolation to x = 1 gives the transition enthalpy of C-type to cubic fluorite YO1.5 as 22.2 ± 6.7 kJ/mol. This linear behavior is in contrast to the strong curvature seen in the ZrO2 - YO1.5 and HfO2 - YO1.5 systems. The slightly positive enthalpy of formation of CeO2 - YO1.5 is strikingly different from the strongly negative enthalpies of formation of ZrO2 - YO1.5 and HfO2 - YO1.5. The thermodynamics of CeO2 - YO1.5 is analyzed in terms of defect association and oxygen vacancy distribution. Specifically, the association of oxygen vacancies with the tetravalent cations in the zirconia and hafnia systems, in contrast to the preference of vacancies for nearest neighbor yttrium sites in the ceria systems, may explain the different energetics.",

author = "Weiqun Chen and Lee, {Theresa A.} and Alexandra Navrotsky",

note = "Funding Information: This work was supported by the U.S. Department of Energy (Grant No. 03ER46053).",

year = "2005",

month = jan,

doi = "10.1557/JMR.2005.0017",

language = "English (US)",

volume = "20",

pages = "144--150",

journal = "Journal of Materials Research",

issn = "0884-2914",

publisher = "Materials Research Society",

number = "1",

}

TY - JOUR

T1 - Enthalpy of formation of yttria-doped ceria

AU - Chen, Weiqun

AU - Lee, Theresa A.

AU - Navrotsky, Alexandra

N1 - Funding Information: This work was supported by the U.S. Department of Energy (Grant No. 03ER46053).

PY - 2005/1

Y1 - 2005/1

N2 - Solid solutions (1 - x)CeO2 - xYO1.5 (0 ≤ × ≤ 0.36) were prepared by coprecipitation and sol-gel methods. Their enthalpy of formation relative to the end-members, fluorite-type cubic CeO2 and C-type YO1.5 was determined by oxide melt solution calorimetry. The enthalpy of drop solution shows a roughly linear trend with composition. Extrapolation to x = 1 gives the transition enthalpy of C-type to cubic fluorite YO1.5 as 22.2 ± 6.7 kJ/mol. This linear behavior is in contrast to the strong curvature seen in the ZrO2 - YO1.5 and HfO2 - YO1.5 systems. The slightly positive enthalpy of formation of CeO2 - YO1.5 is strikingly different from the strongly negative enthalpies of formation of ZrO2 - YO1.5 and HfO2 - YO1.5. The thermodynamics of CeO2 - YO1.5 is analyzed in terms of defect association and oxygen vacancy distribution. Specifically, the association of oxygen vacancies with the tetravalent cations in the zirconia and hafnia systems, in contrast to the preference of vacancies for nearest neighbor yttrium sites in the ceria systems, may explain the different energetics.

AB - Solid solutions (1 - x)CeO2 - xYO1.5 (0 ≤ × ≤ 0.36) were prepared by coprecipitation and sol-gel methods. Their enthalpy of formation relative to the end-members, fluorite-type cubic CeO2 and C-type YO1.5 was determined by oxide melt solution calorimetry. The enthalpy of drop solution shows a roughly linear trend with composition. Extrapolation to x = 1 gives the transition enthalpy of C-type to cubic fluorite YO1.5 as 22.2 ± 6.7 kJ/mol. This linear behavior is in contrast to the strong curvature seen in the ZrO2 - YO1.5 and HfO2 - YO1.5 systems. The slightly positive enthalpy of formation of CeO2 - YO1.5 is strikingly different from the strongly negative enthalpies of formation of ZrO2 - YO1.5 and HfO2 - YO1.5. The thermodynamics of CeO2 - YO1.5 is analyzed in terms of defect association and oxygen vacancy distribution. Specifically, the association of oxygen vacancies with the tetravalent cations in the zirconia and hafnia systems, in contrast to the preference of vacancies for nearest neighbor yttrium sites in the ceria systems, may explain the different energetics.

UR - http://www.scopus.com/inward/record.url?scp=19944392326&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=19944392326&partnerID=8YFLogxK

U2 - 10.1557/JMR.2005.0017

DO - 10.1557/JMR.2005.0017

M3 - Article

AN - SCOPUS:19944392326

SN - 0884-2914

VL - 20

SP - 144

EP - 150

JO - Journal of Materials Research

JF - Journal of Materials Research

IS - 1

ER -

Enthalpy of formation of yttria-doped ceria

Abstract

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this