• Journal of the Korean Ceramic Society
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• v.39 no.4
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• pp.346-351
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• 2002

The electrical conductivity and phase stability of $ZrO_2$ doped with $Sc_2O_3$ and $CeO_2$ were investigated in order to search for better solid electrolyte material for solid oxide fuel cell. Present study showed that $ZrO_2$ doped with $Sc_2O_3$ and $CeO_2$ exhibited no phase transition during the heat treatment up to $1350^{Circ}C∼1550^{Circ}C$ and was stable as a cubic phase in whole temperature ranges. The $ZrO_2$ doped with $Sc_2O_3$ and $CeO_2$ showed much higher electrical conductivity than YSZ in the temperature range of $300∼^{Circ}C$ and better long term stability than other sc-$ZrO_2$ based electrolyte that showed the possibility as a strong candidate electrolyte material for intermediate-or low-temperature SOFC.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.4
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• pp.555-559
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• 1997

Lead scandium niobate $Pb(Sc_{1/2}Nb_{1/2})O_3$ powders were prepared by the sol-gel method using lead acetate, scandium acetate, and niobium isopropoxide as precursors. Crystallization behavior and phase formation were investigated for gel-derived powders. After the calcination at $700^{\circ}C$ for 1 hr, $Pb(Sc_{1/2}Nb_{1/2})O_3$ powder with the purity of 97% was formed and the average particle size of powder was below 0.2 $\mu \textrm{m}$.

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.111.2-111
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• 2002

• Journal of the Korean Ceramic Society
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• v.53 no.5
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• pp.500-505
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• 2016

Scandia-stabilized zirconia co-doped with $CeO_2$ is a promising electrolyte for intermediate temperature SOFC, but still shows rapid degradation during a long-term operation. In this study, $CeO_2$ (1 mol%) as a stabilizer is partially substituted with lanthanum oxides ($M_2O_3$, M=Yb, Gd, Sm) to stabilize a cubic phase and thus durability in reducing atmosphere. 0.5M0.5Ce10ScSZ electrolytes were prepared by solid state reaction and sintered at $1450^{\circ}C$ for 10 h to produce dense ceramic specimens. With addition of the lanthanum oxide, 0.5M0.5Ce10ScSZ showed lower degradation rates than 1Ce10ScSZ. Since $Gd_2O_3$ showed the highest ionic conductivity among the co-dopants, an electrolyte-supported cell with 0.5Gd0.5Ce10ScSZ was prepared to compare its long-term performance with that of 1Ce10ScSZ-based cell. Maximum power density of 0.5Gd0.5Ce10ScSZ-based cell was degraded by about 2.3% after 250 h, which was much lower than 1Ce10ScSZ-based cell (4.2%).

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.3
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• pp.99-103
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• 2005

Lead scandium tantalate powders were prepared by a molten salt synthesis method using NaCl-KCl as a flux. Variations in phase formation and particle morphology were investigated for the temperature range from $700^{\circ}C\;to\;800^{\circ}C$. $Pb(Sc_{1/2}Ta_{1/2})O_3$, with pure perovskite phase was formed at $750^{\circ}C$ fur 2 hrs and the prepared powder had the cubic-like morphology and the average particle size below $0.5{\mu}m$. The results were discussed with respect to DTA, X-ray diffraction, and microstructural characterization data.

• Applied Science and Convergence Technology
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• v.25 no.4
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• pp.77-80
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• 2016

The $PbSc_{1/2}Nb_{1/2}O_3$ ceramics at a relatively low temperature of $1300^{\circ}C$ was successful synthesized. Solid state reaction of two-step process is not necessary. The dielectric constant, dielectric loss and admittance of ceramic samples were determined. The pyroelectric characteristics are in good agreement with the dielectric properties. Ferroelectric properties of well-formed the $PbSc_{1/2}Nb_{1/2}O_3$ ceramics are in agreement with broad distribution of relaxation phenomenon. Relatively strong frequency dependent of dielectric constant is observed at about $110^{\circ}C$. The distinct thermal hysteresis was observed in the measurement of the dielectric constant and dielectric loss. The critical exponents of during cooling and heating measurements in the $PbSc_{1/2}Nb_{1/2}O_3$ ceramics were 1.14 and 1.59 at 1 kHz, respectively.

• Journal of the Korean Ceramic Society
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• v.36 no.12
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• pp.1287-1295
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• 1999

• Journal of the Korean Ceramic Society
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• v.38 no.11
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• pp.993-999
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• 2001

Phase formation and proton conduction in BaO doped LaSc $O_3$with perovskite structure were studied. L $a_{0.6}$B $a_{0.4}$Sc $O_{2.8}$, viz. 40at% $Ba^{2+}$ ion doped composition, showed a single cubic phase, while the other compositions doped less than 30 at% $Ba^{2+}$ ion showed the cubic phase and the orthorhombic one. Above $650^{\circ}C$ oxygen ion conduction was dominant in $N_2$atmosphere and below this temperature proton conduction was observed in wet atmosphere. All compositions were found to be the pure proton conductors below 30$0^{\circ}C$. The proton conductivity (bulk) of L $a_{0.6}$B $a_{0.4}$Sc $O_{2.8}$ was higher than those of any other composition.osition.ion.

• Journal of the Korean Ceramic Society
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• v.42 no.12 s.283
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• pp.787-792
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• 2005

A symmetrical LSCF $(La_{0.6}Sr_{0.4}Co_{0.2}Fe_{0.8}O_{3-\delta})\;ScSZ(89ZrO_2-10Sc_2O_3-1CeO_2)/LSCF$ electrochemical cell with a GDC (Gadolinium-Doped Ceria, $90CeO_2-10Gd_2O_3$) interlayer that was inserted between the LSCF cathode and ScSZ electrolyte was fabricated, and the electrochemical performance of these cells was evaluated. The GDC interlayer was deposited on a ScSZ electrolyte using a screen-printing technique. The GDC interlayer prevented the unfavorable solid-state reactions at the LSCF/ScSZ interfaces. The LSCF cathode on the GDC interlayer had excellent electrocatalytic performance even at $650^{\circ}C$. The Area Specific Resistance (ASR) was strongly dependent on the thickness and heat-treatment temperature of the GDC interlayer. The impedance spectra showed that the cell with a $15\~27{\mu}m$ thick GDC interlayer heat-treated at $1200^{\circ}C$ had the lowest ASR.

• 한국전기화학회:학술대회논문집
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• 2004.10a
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• pp.35-35
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• 2004