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Title: Silver-Perovskite Composite SOFC Cathodes Processed via Mechanofusion

Abstract

Atomized silver spheres (≈20-50 μm diameter) were coated with 1 micron thick layers of (La 0.6Sr 0.4) 0.98Co 0.2Fe 0.8O 3 or Sm 0.5Sr 0.5CoO 3 via a mechanofusion dry processing method. The materials were subsequently assessed as solid oxide fuel cell cathodes on anode-supported YSZ electrolytes at 650-750ºC. The materials were subject to significant electrochemical conditioning during initial cell operation, and factors , such as temperature and operating voltage, affecting the conditioning rate are discussed. Post-conditioned power densities (at 0.7 V) were typically 550-650, 400-450 and 300-350 mWcm ₋2 at 750, 700 and 650ºC, respectively. Though power degradation rates of ≈7.5 and 4.5% (per 1000 h) were observed at 750 and 700ºC, respectively, no degradation was detected over almost 2000 hours of testing at 650ºC.

Authors:
; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
918458
Report Number(s):
PNNL-SA-53756
AA2530000
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Power Sources, 168(1):236-239
Country of Publication:
United States
Language:
English
Subject:
sofc, cathode

Citation Formats

Simner, Steven P, Anderson, Michael D, Templeton, Jared W, and Stevenson, Jeffry W. Silver-Perovskite Composite SOFC Cathodes Processed via Mechanofusion. United States: N. p., 2007. Web. doi:10.1016/j.jpowsour.2007.03.029.
Simner, Steven P, Anderson, Michael D, Templeton, Jared W, & Stevenson, Jeffry W. Silver-Perovskite Composite SOFC Cathodes Processed via Mechanofusion. United States. doi:10.1016/j.jpowsour.2007.03.029.
Simner, Steven P, Anderson, Michael D, Templeton, Jared W, and Stevenson, Jeffry W. Fri . "Silver-Perovskite Composite SOFC Cathodes Processed via Mechanofusion". United States. doi:10.1016/j.jpowsour.2007.03.029.
@article{osti_918458,
title = {Silver-Perovskite Composite SOFC Cathodes Processed via Mechanofusion},
author = {Simner, Steven P and Anderson, Michael D and Templeton, Jared W and Stevenson, Jeffry W},
abstractNote = {Atomized silver spheres (≈20-50 μm diameter) were coated with 1 micron thick layers of (La0.6Sr0.4)0.98Co0.2Fe0.8O3 or Sm0.5Sr0.5CoO3 via a mechanofusion dry processing method. The materials were subsequently assessed as solid oxide fuel cell cathodes on anode-supported YSZ electrolytes at 650-750ºC. The materials were subject to significant electrochemical conditioning during initial cell operation, and factors , such as temperature and operating voltage, affecting the conditioning rate are discussed. Post-conditioned power densities (at 0.7 V) were typically 550-650, 400-450 and 300-350 mWcm₋2 at 750, 700 and 650ºC, respectively. Though power degradation rates of ≈7.5 and 4.5% (per 1000 h) were observed at 750 and 700ºC, respectively, no degradation was detected over almost 2000 hours of testing at 650ºC.},
doi = {10.1016/j.jpowsour.2007.03.029},
journal = {Journal of Power Sources, 168(1):236-239},
number = ,
volume = ,
place = {United States},
year = {Fri May 25 00:00:00 EDT 2007},
month = {Fri May 25 00:00:00 EDT 2007}
}
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