Sintering, Electrical Conductivity, Oxygen Nonstoichiometry, Thermal Expansion and Thermal Stability of Ruddlesden-Popper Type Cobaltite La4Co3O10
Sintering, Electrical Conductivity, Oxygen Nonstoichiometry, Thermal Expansion and Thermal Stability of Ruddlesden-Popper Type Cobaltite La4Co3O10
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DOI：
10.1149/2.0811609jes
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发表时间：
2016
影响因子：
3.9
通讯作者：
Yoshinobu Adachi;Naoyuki Hatada;T. Uda
中科院分区：
文献类型：
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作者：
Yoshinobu Adachi;Naoyuki Hatada;T. Uda
由于La4Co3O10与典型的LaCoO3正极材料相似，因此La4Co3O10具有良好的正极性能。然而，La4Co3O10的稳定氧分压(PO2)范围较窄，这给La4Co3O10的合成和烧结带来了困难，其电学和离子性质还没有得到充分的研究。本研究利用Fe2 O3和Fe3O4之间的平衡，将烧结过程中的pO2控制在稳定的范围内，制备出致密的La4Co3O10。La4Co3O10的导电性与LSCF等钙钛矿型正极材料相当。氧的非化学计量比是超化学计量比。此外，在空气中，La4Co3O10在800℃或更高的温度下在100h内部分分解为LaCoO3和La2O 3，而在700℃或更低的温度下没有检测到分解产物。
A favorable cathode performance can be expected with La 4 Co 3 O 10, due to the similarity to the representative cathode material of LaCoO 3. However, its narrow stable oxygen partial pressure (p O2) range has made it difficult to synthesize and sinter La 4 Co 3 O 10, and its electrical and ionic properties has not yet been studied enough. In this study, the dense body of La 4 Co 3 O 10 was prepared by controlling p O2 during sintering within its stable range utilizing the equilibrium between Fe 2 O 3 and Fe 3 O 4. The electrical conductivity of La 4 Co 3 O 10 is comparable to those of perovskite-type cathode materials such as LSCF. And its oxygen nonstoichiometry is hyperstoichiometric. Additionally, it was revealed that in air La 4 Co 3 O 10 partially decomposes to LaCoO 3 and La 2 O 3 in 100 h at 800 C or higher, while no decomposition product was detected by X-ray diffraction at 700 C or lower.