Evaluation of performance and durability of Ni-BZY cermet electrodes with BZY electrolyte

Onishi, Takayuki; Han, Donglin; Noda, Yohei; Hatada, Naoyuki; Majima, Masatoshi; Uda, Tetsuya

doi:10.1016/j.ssi.2018.01.015

Cited by 35 publications

(24 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However,a nother important reason could be the successfulp reparation of at hin electrolyte layer without NiO. [59,60] Bae et al [32] inserted af unctional layer composed of nanometersized BZY15 and NiO particles between the electrolyte and the anode layers. [23] and Bae et al [32] were estimated to be 0.00021 and 0.00278 Scm À1 ,r espectively.H owever, these values were far lower than the conductivity of the pellet sample.…”

Section: Currentfabrication Methods Of Anode-supported Cells and Perspmentioning

confidence: 99%

“…One reason could be the off-stoichiometry and another reasonc ould be the ohmic resistance in the electrode layers.T he anode substrate in the work of Pergolesi, et al [23] containedo nly 26 wt %N iO, far from the appropriate NiO content of approximately 40-70 wt %. [59,60] Bae et al [32] inserted af unctional layer composed of nanometersized BZY15 and NiO particles between the electrolyte and the anode layers. Therefore, the measured ohmic resistance may not solely reflectt he contributionf rom the electrolyte layer.A t present, the PLD method is still expensive and not suitablef or the deposition of thin films at al arge scale.…”

Section: Currentfabrication Methods Of Anode-supported Cells and Perspmentioning

confidence: 99%

See 1 more Smart Citation

Detrimental Effect of Sintering Additives on Conducting Ceramics: Yttrium‐Doped Barium Zirconate

et al. 2018

Self Cite

View full text Add to dashboard Cite

Y-doped BaZrO (BZY) is currently the most promising proton-conductive ceramic-type electrolyte for application in electrochemical devices, including fuel cells and electrolyzer cells. However, owing to its refractory nature, sintering additives, such as NiO, CuO, or ZnO are commonly added to reduce its high sintering temperature from 1600 °C to approximately 1400 °C. Even without deliberately adding a sintering additive, the NiO anode substrate provides another source of the sintering additive; during the co-sintering process, NiO diffuses from the anode into the BZY electrolyte layer. In this work, a systematic study of the effect of NiO, CuO, and ZnO on the electroconductive properties of BaZr Y O (BZY20) is conducted. The results revealed that the addition of NiO, CuO, or ZnO into BZY20 not only degraded the electrical conductivity but also resulted in enhancement of the hole conduction. Removal of these sintering additives can be realized by post-annealing in hydrogen at a mild temperature of 700 °C, but it is kinetically very slow. Therefore, the addition of NiO, CuO, and ZnO is detrimental to the electroconductive properties of BZY20, and significantly restrict its application as an electrolyte. The development of new sintering additives, new anode catalysts, or new methods for preparing BZY electrolyte-based cells is urgently needed.

show abstract

Section: Currentfabrication Methods Of Anode-supported Cells and Perspmentioning

confidence: 99%

Section: Currentfabrication Methods Of Anode-supported Cells and Perspmentioning

confidence: 99%

Detrimental Effect of Sintering Additives on Conducting Ceramics: Yttrium‐Doped Barium Zirconate

et al. 2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…A recent study focused on the preparation on Ni/BZY20 anodes, varying the amount of NiO [414]. The co-sintering of the BZY20 onto BZY20/NiO supports failed for 80 wt.% of NiO, due to the difference in thermal expansion coefficients between NiO and BZY20.…”

Section: Expansion Of Fuel Side Electrodesmentioning

confidence: 99%

“…The hydration of BZY/NiO supports with BZY thin membranes is very critical. Onishi et al reported that the hydration of BZY20 should be carried out at higher temperatures to alleviate compressive stress [414]. This observation is based on the observation of cells (60 wt.%NiO/BZY20 with thin BZY20 electrolyte) heated to 100 or 200 • C in dry Ar and then up to 600 • C in 3% H 2 O in Ar.…”

Section: Expansion Of Fuel Side Electrodesmentioning

confidence: 99%

Thermal and Chemical Expansion in Proton Ceramic Electrolytes and Compatible Electrodes

2018

View full text Add to dashboard Cite

This review paper focuses on the phenomenon of thermochemical expansion of two specific categories of conducting ceramics: Proton Conducting Ceramics (PCC) and Mixed Ionic-Electronic Conductors (MIEC). The theory of thermal expansion of ceramics is underlined from microscopic to macroscopic points of view while the chemical expansion is explained based on crystallography and defect chemistry. Modelling methods are used to predict the thermochemical expansion of PCCs and MIECs with two examples: hydration of barium zirconate (BaZr1−xYxO3−δ) and oxidation/reduction of La1−xSrxCo0.2Fe0.8O3−δ. While it is unusual for a review paper, we conducted experiments to evaluate the influence of the heating rate in determining expansion coefficients experimentally. This was motivated by the discrepancy of some values in literature. The conclusions are that the heating rate has little to no effect on the obtained values. Models for the expansion coefficients of a composite material are presented and include the effect of porosity. A set of data comprising thermal and chemical expansion coefficients has been gathered from the literature and presented here divided into two groups: protonic electrolytes and mixed ionic-electronic conductors. Finally, the methods of mitigation of the thermal mismatch problem are discussed.

show abstract

“…Due to high proton conductivity (eg, >0.01 Scm −1 at 450°C) [1][2][3][4][5] and excellent chemical stability, [6][7][8] Y-doped BaZrO 3 (BaZr 1−x Y x O 3−δ , BZY) is a promising electrolyte candidate in electrochemical devices, including fuel cells [9][10][11][12][13] and electrolysis cells. 14,15 With the aim to facilitate the cell fabrication, transition metal element oxides were usually added into the BZY electrolyte.…”

Section: Introductionmentioning

confidence: 99%

Electrochemical and structural influence on BaZr_0.8Y_0.2O_3‐δ from manganese, cobalt, and iron oxide additives

et al. 2019

Self Cite

View full text Add to dashboard Cite

Proton conductive BaZr0.8Y0.2O3−δ (BZY20) is a promising electrolyte candidate with perspective application in electrochemical devices, including fuel cells, electrolyzer cells. Mn, Fe, and Co are commonly incorporated into BZY20, to improve the sinterability (CoO), or due to possible inter‐diffusion by calcining with cathode materials (eg, La1−xSrxMnO3−δ, La1−xSrxCo1−yFeyO3−δ) for cell preparation. This work was performed to investigate the influence of Mn, Fe, and Co on the structural and electrochemical properties of BZY20. As reported in literature, the sinterability of BZY20 was improved by adding CoO. XANES analysis shows that Mn, Fe, and Co are possibly incorporated into the perovskite crystal structure of BZY20, and are partially reduced when the samples were exposed to hydrogen at 600°C for 24 hours. However, through electrochemical analysis, we found that all these three elements decrease both the proton conductivity and transport numbers of proton conduction of BZY20. Therefore, the BZY20 electrolyte should be carefully handled to avoid the incorporation of these transition metal elements, to fabricate the cells with high performance.

show abstract

Evaluation of performance and durability of Ni-BZY cermet electrodes with BZY electrolyte

Cited by 35 publications

References 44 publications

Detrimental Effect of Sintering Additives on Conducting Ceramics: Yttrium‐Doped Barium Zirconate

Detrimental Effect of Sintering Additives on Conducting Ceramics: Yttrium‐Doped Barium Zirconate

Thermal and Chemical Expansion in Proton Ceramic Electrolytes and Compatible Electrodes

Electrochemical and structural influence on BaZr_0.8Y_0.2O_3‐δ from manganese, cobalt, and iron oxide additives

Contact Info

Product

Resources

About

Evaluation of performance and durability of Ni-BZY cermet electrodes with BZY electrolyte

Cited by 35 publications

References 44 publications

Detrimental Effect of Sintering Additives on Conducting Ceramics: Yttrium‐Doped Barium Zirconate

Detrimental Effect of Sintering Additives on Conducting Ceramics: Yttrium‐Doped Barium Zirconate

Thermal and Chemical Expansion in Proton Ceramic Electrolytes and Compatible Electrodes

Electrochemical and structural influence on BaZr0.8Y0.2O3‐δ from manganese, cobalt, and iron oxide additives

Contact Info

Product

Resources

About

Electrochemical and structural influence on BaZr_0.8Y_0.2O_3‐δ from manganese, cobalt, and iron oxide additives