• Proceedings of the Materials Research Society of Korea Conference
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• 1996.05a
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• pp.21-21
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• 1996

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1258-1260
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• 1997

The metallic interconnector has a superior property than the ceramic interconnector in the point of the cell performance, but has problems to form oxide films on the interconnector surface during cell operation and induce cracking in the cell due to the stress by the thermal expansion coefficient difference with stabilized Zr electrolyte. For solving the problems in the metallic interconnector, new and modified materials have been investigated. In this paper, $LaCrO_3$ dispersed Cr was evaluated in high temperature oxidized characteristics, sintering density, electrical conductivity and various thermochemical properties. The test results show that $LaCrO_3$ dispersed Cr has more superior properties than that of conventional alloy interconnector and $LaCrO_3$ dispersed Cr can be used as an interconnector in SOFC.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.96.1-96.1
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• 2012

SOFC는 다른 연료전지보다 상대적으로 높은 구동 온도를 가지며 그로인해 높은 에너지 효율을 가진다. 먼저 금속연결제의 경우 높은 고온에서 산화 반응이 쉽게 일어나기 때문에 이로 인하여 연결재의 주요 특성인 전기전도도의 감소와 부피변화로 인한 크랙등이 유발되어 연결재의 주요 기능인 전기적인 연결 뿐만 아니라, 물리적으로 양극과 음극의 차폐 또한 어려워져 장기 구동에 있어서 주요 결함의 원인이되고 있다. 이로 인하여 많은 세라믹 연결재의 개발이 진행되어왔고, 이중에서 perovskite-structure를 가지는 LCO계의 연결재에 대한 연구가 활발히 진행되고 있다. $LaCrO_3$는 열팽창 계수가 주요 구성소재들과 유사하다는 장점과 도핑과 친환으로 인하여 특성제어가 용이하다는 이유 때문에 주로 사용되고 있다. 그러나 $LaCrO_3$는 낮은 전기전도도와 높은 소결온도에서 Cr휘발되는 단점이 있다. 이를 해결하기 위해서 A에 희토류와 B-site에 전위금속을 치환하여 소결 온도를 낮춘 연구들이 진행 되었다. 본 연구에서는 이런 결과 중 $La_{0.7}Ca_{0.3}Cr_{0.9}Co_{0.1}O_3$조성에 소결조제를 첨가하여 그에 따른 특성변화를 관찰하였다.

• Journal of the Korean Ceramic Society
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• v.52 no.5
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• pp.308-314
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• 2015

The electrochemical performance and Cr poisoning behavior of $La_{1-x}Ba_xCo_{0.9}Fe_{0.1}O_{3-{\delta}}$ (LBCF, x = 0.3, 0.4, 0.5) and $La_{0.6}Sr_{0.4}Co_{0.2}Fe_{0.8}O_{3-{\delta}}$ (LSCF) cathodes were investigated for solid oxide fuel cells (SOFCs). The polarization resistance of the LBCF/GDC/LBCF symmetrical cell was found to decrease with increasing Ba content (x value). This phenomenon might be associated with the high oxygen vacancy concentration in the LBCF sample, with x = 0.5. In addition, there was no chromium poisoning in the LBCF cathode. On the other hand, the polarization resistance of the LSCF cathode was found to significantly increase after exposure to gaseous chromium species; it appears that this result stemmed from the formation of $SrCrO_4$ phase. Therefore, it can be expected that LBCF can be a durable potential cathode material for intermediate-temperature solid oxide fuel cells (IT-SOFC).

• 한국전기화학회:학술대회논문집
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• 2004.04a
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• pp.3-3
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• 2004

• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.697-702
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• 2011

The new layered perovskite manganites $La_{0.5}Sr_{1.5}Mn_{0.5}Cr_{0.5-x}Fe_xO_4$ (x=0.15, 0.3) have been prepared by standard ceramic method. The powder X-ray diffraction studies show that the phases crystallize with tetragonal unit cell in the space group I4/mmm. The electrical transport properties suggest that the phases show insulating behaviour and the electrical conduction in the phases occurs by a 3D variable range hopping mechanism. The magnetic properties suggest that both the phases are antiferromagnetic.

• 한국전기화학회:학술대회논문집
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• 2002.07a
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• pp.277-280
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• 2002

• 한국전기화학회:학술대회논문집
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• 2001.06a
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• pp.255-258
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• 2001

• Proceedings of the Materials Research Society of Korea Conference
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• 2006.11a
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• pp.32.2-32.2
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• 2006

• Journal of the Korean Ceramic Society
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• v.43 no.9 s.292
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• pp.558-563
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• 2006

The electrical and dielectric properties of $ZnO-Pr_6O_{11}CoO-Cr_2O_3La_2O_3-based$ nonlinear resistors were investigated at different sintering temperatures in the range of $1230{\sim}1300^{|circ}C$. As the sintering temperature increased, the breakdown voltage decreased from 777.9 to 108.0V/mm, the nonlinear coefficient greatly decreased from 77.0 to 7.1, and the leakage current increased from $0.4{\mu}A\;to\;50.6{\mu}A$. On the other hand, the donor density from $0.90{\times}10^{18}\;to\;2.59{\times}10^{18}/cm^3$ and the barrier height decreased from 1.89 to 0.69 eV with increasing temperature. The dielectric dissipation factor increased from 0.0879 to 0.2839 for the increase of sintering temperature.