Effect of Sr on Sm-doped ceria electrolyte

Zheng, Yifeng; He, Shoucheng; Ge, Lin; Zhou, Ming; Chen, Han; Guo, Lucun

doi:10.1016/j.ijhydene.2011.01.042

Cited by 82 publications

(40 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[37][38][39] It should be noted here that the densification observed in this experiment is not as pronounced as that observed when the SDC is in contact with the LSCF cathode for only 2 hours at 1200…”

mentioning

confidence: 51%

SrZrO₃Formation at the Interlayer/Electrolyte Interface during (La_1-xSr_x)_1-δCo_1-yFe_yO₃Cathode Sintering

Darvish

Hardy

et al. 2017

J. Electrochem. Soc.

View full text Add to dashboard Cite

This work probes the formation of SrZrO 3 at the SDC/YSZ interface (Sm doped ceria, SDC; Y stabilized zirconia, YSZ) during (La 1-x Sr x ) 1-δ Co 1-y Fe y O 3 (LSCF) cathode sintering. SEM/EDS and grazing incidence X-ray diffraction results of annealed LSCF and YSZ samples reveal that even without physical contact between LSCF and YSZ, SrZrO 3 was formed on the surface of YSZ, preferentially at the grain boundaries. It was suspected that the SrZrO 3 formation is due to the Sr-containing gas species diffused through the pores of the SDC layer and reacted with the YSZ electrolyte. Computational thermodynamics was adopted to predict the gas species formed in air during sintering by using the La-Sr-Co-Fe-O-H thermodynamic database. Sr(OH) 2 is identified as the dominant Sr-containing gas species under the experimental conditions. In addition, it was found that A-site deficiency in LSCF could effectively suppress the SrZrO 3 formation while a dense and pore-free SDC interlayer is required to totally block the SrZrO 3 formation. Cell performance was significantly improved for a cell with a dense SDC interlayer fabricated by pulsed laser deposition, due to elimination of SrZrO 3 formation and therefore reduced interfacial resistance. • C). LSCF materials exhibit electrochemical activity toward oxygen reduction that is superior to Sr-doped LaMnO 3 (LSM), an SOFC cathode material widely used at temperatures above 800• C. 1-8 However, LSCF materials also show higher chemical reactivity with the state-of-the-art electrolyte material, yttria stabilized zirconia (YSZ), than LSM. Reports have shown that LSCF reacts with YSZ to form an insulating La 2 Zr 2 O 7 (LZO) or SrZrO 3 (SZO) layer between the cathode and electrolyte at temperatures as low as 900• C, while LSM essentially does not react with YSZ until 1200• C. 9-16 Therefore, for LSCF to be used as a cathode, an interlayer is necessary between the cathode and electrolyte to prevent these detrimental reactions from occurring during cathode sintering and cell operation. Sm-or Gd-doped ceria (SDC or GDC) is usually used as the interlayer because it is chemically compatible with both the LSCF cathode and the YSZ electrolyte at high temperatures. 2,5,[9][10][11]14 An interlayer of high density is desirable to reduce the ohmic resistance in the interlayer. The sinterability of the SDC interlayer is influenced by several factors, such as the method of fabrication, initial particle size, sintering temperature, etc. Fuel cells with a dense doped ceria interlayer fabricated by either pulsed laser deposition or magnetron sputtering show a pronounced increase in power density. 17,18The significant increase in power density is attributed to decreased ohmic resistance, due to the improved density of the interlayer, better interfacial contact between the SDC and YSZ layers, and decreased insulating reaction products at this interface. Interlayers fabricated by other methods such as screen printing, dip coating, tape casting, or spray coating usually contain a certain amount of porosit...

show abstract

mentioning

confidence: 51%

SrZrO₃Formation at the Interlayer/Electrolyte Interface during (La_1-xSr_x)_1-δCo_1-yFe_yO₃Cathode Sintering

Darvish

Hardy

et al. 2017

J. Electrochem. Soc.

View full text Add to dashboard Cite

show abstract

“…Furthermore, it is observed that substitution of Mg in SDC increases the relative density. The relative density of 5SMC11 is comparable with that of 20SDC14, which shows that the alkali earth metals can be used as sintering aid in ceria ceramics (Zheng et al 2011). The cross-sectional micrograph of 20SDC14 pellet in Fig.…”

Section: Densitymentioning

confidence: 69%

Effect of Mg doping and sintering temperature on structural and morphological properties of samarium-doped ceria for IT-SOFC electrolyte

et al. 2017

View full text Add to dashboard Cite

Samples of Sm and Mg co-doped ceria electrolyte of Ce 1-x Sm x-y Mg y O 2-d (x = 0.2; y = 0.00, 0.05, 0.1, 0.15, and 0.175) were synthesized by sol-gel process. The prepared samples were sintered at 1100 and 1400°C for 4 h. The bulk densities were measured by Archimedes method. XRD measurements indicate that the synthesized samples were in single-phase cubic fluorite structure (space group Fm3m). The cell parameters decrease with the concentration of Mg, and 2h values slightly shift towards right. The particle sizes obtained were between 7.14 and 17.44 nm. The sintered sample achieved 95% of theoretical density. FTIR spectra of samples sintered at 1400°C indicates weak interactions between 3550-3400 cm -1 and 1600-1300 cm -1 are attributed to O-H stretching modes and strong bonds 850-450 cm -1 are assigned to characteristic Ce-O vibrations. The surface morphology and chemical composition were analyzed by SEM and EDS, SEM micrographs show spherical faceted grains, and the samples were crack free, dense material with some pores on surface which are inconsistent with density results. The average grain size obtained was 0.5 lm. Particle size obtained by TEM was in agreement with that obtained by XRD. The high-density ceria co-doped ceramic can be used as electrolyte in SOFC.

show abstract

“…7 shows the Arrhenius plots of the electrical conductivities of the samples from 300 to 750 C. The Arrhenius curve cannot be fitted by a straight line; instead, it is fitted by two straight lines for the low and highetemperature regimes. The transition in the slope is at 600 C. Similar approaches have been adopted in previous reports [12,21] and researchers believe that the conduction mechanism in the lowetemperature regime differs from the highetemperature i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 7 ( 2 0 1 2 ) 1 6 1 2 3 e1 6 1 2 9 regime. The data can be analyzed by the traditional Arrhenius equation:…”

Section: Electrical Conductivitymentioning

confidence: 80%

“…However, the refractory nature of doped ceria leads to significant challenges in its implementation in SOFCs [9,10]. Several transition metal oxides, such as Fe 2 O 3 [11], SrO [12] and ZnO [13,14], reportedly improve the sinterability of doped ceria effectively. Chen and Chen [15] found that TiO 2 addition enhances grain boundary mobility at 0.1 mol% levels.…”

Section: Introductionmentioning

confidence: 99%

Effect of titania concentration on the grain boundary conductivity of Ce0.8Gd0.2O1.9 electrolyte

et al. 2012

International Journal of Hydrogen Energy

Self Cite

View full text Add to dashboard Cite

Effect of Sr on Sm-doped ceria electrolyte

Cited by 82 publications

References 52 publications

SrZrO₃Formation at the Interlayer/Electrolyte Interface during (La_1-xSr_x)_1-δCo_1-yFe_yO₃Cathode Sintering

SrZrO₃Formation at the Interlayer/Electrolyte Interface during (La_1-xSr_x)_1-δCo_1-yFe_yO₃Cathode Sintering

Effect of Mg doping and sintering temperature on structural and morphological properties of samarium-doped ceria for IT-SOFC electrolyte

Effect of titania concentration on the grain boundary conductivity of Ce0.8Gd0.2O1.9 electrolyte

Contact Info

Product

Resources

About

Effect of Sr on Sm-doped ceria electrolyte

Cited by 82 publications

References 52 publications

SrZrO3Formation at the Interlayer/Electrolyte Interface during (La1-xSrx)1-δCo1-yFeyO3Cathode Sintering

SrZrO3Formation at the Interlayer/Electrolyte Interface during (La1-xSrx)1-δCo1-yFeyO3Cathode Sintering

Effect of Mg doping and sintering temperature on structural and morphological properties of samarium-doped ceria for IT-SOFC electrolyte

Effect of titania concentration on the grain boundary conductivity of Ce0.8Gd0.2O1.9 electrolyte

Contact Info

Product

Resources

About

SrZrO₃Formation at the Interlayer/Electrolyte Interface during (La_1-xSr_x)_1-δCo_1-yFe_yO₃Cathode Sintering

SrZrO₃Formation at the Interlayer/Electrolyte Interface during (La_1-xSr_x)_1-δCo_1-yFe_yO₃Cathode Sintering