Design of electroceramics for solid oxides fuel cell applications: Playing with ceria

Vincenzo Esposito, Enrico Traversa

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Nanostructured samaria- and gadolinia-doped ceria (SDC and GDC) powders were synthesized at low temperature (400°C) using diamine-assisted direct coprecipitation method. Fast-firing (f.f.) processes, where sintering temperatures are reached in a short time to promote lattice diffusion, were compared with conventional sintering, for the formation of dense microstructures from the nanostructured powders. Highly dense SDC and GDC samples (96%) with reduced grain size (150 nm) were obtained by f.f. even at 1300°-1400°C and, unexpectedly, high electrical conductivity and low blocking effect at grain boundary was obtained. Conventionally sintered samples showed that the grain boundary resistivity decreased with increasing the grain size, in agreement with the increase in geometrical bulk volume/grain boundary area ratio. Conversely, f.f. samples showed grain boundary resistivity smaller for small grain size. The above effect was observed only for high dopant (>10% molar) contents. The combined effect of powder grain size, dopant content, and sintering temperature-time profile, can be exploited to tune ceria microstructures for specific ionic device applications. © 2008 The American Ceramic Society.
Keyword: Diamine-assisted direct coprecipitation method,Sintering temperatures,Nanostructured materials,Electroceramics,Solid oxide fuel cells (SOFC)
Original languageEnglish
JournalJournal of the American Ceramic Society
Volume91
Issue number4
Pages (from-to)1037-1051
ISSN0002-7820
DOIs
Publication statusPublished - 2008
Externally publishedYes

Cite this

@article{44f62e217e4e4aff837f20dc9316afbb,
title = "Design of electroceramics for solid oxides fuel cell applications: Playing with ceria",
abstract = "Nanostructured samaria- and gadolinia-doped ceria (SDC and GDC) powders were synthesized at low temperature (400°C) using diamine-assisted direct coprecipitation method. Fast-firing (f.f.) processes, where sintering temperatures are reached in a short time to promote lattice diffusion, were compared with conventional sintering, for the formation of dense microstructures from the nanostructured powders. Highly dense SDC and GDC samples (96{\%}) with reduced grain size (150 nm) were obtained by f.f. even at 1300°-1400°C and, unexpectedly, high electrical conductivity and low blocking effect at grain boundary was obtained. Conventionally sintered samples showed that the grain boundary resistivity decreased with increasing the grain size, in agreement with the increase in geometrical bulk volume/grain boundary area ratio. Conversely, f.f. samples showed grain boundary resistivity smaller for small grain size. The above effect was observed only for high dopant (>10{\%} molar) contents. The combined effect of powder grain size, dopant content, and sintering temperature-time profile, can be exploited to tune ceria microstructures for specific ionic device applications. {\circledC} 2008 The American Ceramic Society. Keyword: Diamine-assisted direct coprecipitation method,Sintering temperatures,Nanostructured materials,Electroceramics,Solid oxide fuel cells (SOFC)",
author = "Vincenzo Esposito and Enrico Traversa",
year = "2008",
doi = "10.1111/j.1551-2916.2008.02347.x",
language = "English",
volume = "91",
pages = "1037--1051",
journal = "Journal of the American Ceramic Society",
issn = "0002-7820",
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}

Design of electroceramics for solid oxides fuel cell applications: Playing with ceria. / Esposito, Vincenzo; Traversa, Enrico.

In: Journal of the American Ceramic Society, Vol. 91, No. 4, 2008, p. 1037-1051.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Design of electroceramics for solid oxides fuel cell applications: Playing with ceria

AU - Esposito, Vincenzo

AU - Traversa, Enrico

PY - 2008

Y1 - 2008

N2 - Nanostructured samaria- and gadolinia-doped ceria (SDC and GDC) powders were synthesized at low temperature (400°C) using diamine-assisted direct coprecipitation method. Fast-firing (f.f.) processes, where sintering temperatures are reached in a short time to promote lattice diffusion, were compared with conventional sintering, for the formation of dense microstructures from the nanostructured powders. Highly dense SDC and GDC samples (96%) with reduced grain size (150 nm) were obtained by f.f. even at 1300°-1400°C and, unexpectedly, high electrical conductivity and low blocking effect at grain boundary was obtained. Conventionally sintered samples showed that the grain boundary resistivity decreased with increasing the grain size, in agreement with the increase in geometrical bulk volume/grain boundary area ratio. Conversely, f.f. samples showed grain boundary resistivity smaller for small grain size. The above effect was observed only for high dopant (>10% molar) contents. The combined effect of powder grain size, dopant content, and sintering temperature-time profile, can be exploited to tune ceria microstructures for specific ionic device applications. © 2008 The American Ceramic Society. Keyword: Diamine-assisted direct coprecipitation method,Sintering temperatures,Nanostructured materials,Electroceramics,Solid oxide fuel cells (SOFC)

AB - Nanostructured samaria- and gadolinia-doped ceria (SDC and GDC) powders were synthesized at low temperature (400°C) using diamine-assisted direct coprecipitation method. Fast-firing (f.f.) processes, where sintering temperatures are reached in a short time to promote lattice diffusion, were compared with conventional sintering, for the formation of dense microstructures from the nanostructured powders. Highly dense SDC and GDC samples (96%) with reduced grain size (150 nm) were obtained by f.f. even at 1300°-1400°C and, unexpectedly, high electrical conductivity and low blocking effect at grain boundary was obtained. Conventionally sintered samples showed that the grain boundary resistivity decreased with increasing the grain size, in agreement with the increase in geometrical bulk volume/grain boundary area ratio. Conversely, f.f. samples showed grain boundary resistivity smaller for small grain size. The above effect was observed only for high dopant (>10% molar) contents. The combined effect of powder grain size, dopant content, and sintering temperature-time profile, can be exploited to tune ceria microstructures for specific ionic device applications. © 2008 The American Ceramic Society. Keyword: Diamine-assisted direct coprecipitation method,Sintering temperatures,Nanostructured materials,Electroceramics,Solid oxide fuel cells (SOFC)

U2 - 10.1111/j.1551-2916.2008.02347.x

DO - 10.1111/j.1551-2916.2008.02347.x

M3 - Journal article

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JO - Journal of the American Ceramic Society

JF - Journal of the American Ceramic Society

SN - 0002-7820

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