Characterization of Cathode Materials Ln0.7Sr0.2Ca0.1Co0.7Fe0.3O2.85 (Ln=La, Pr and Nd) Synthesized by Microwave Sintering Techniques

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Abstract:

Sr, Ca and Fe doped cathode materials Ln0.7Sr0.2Ca0.1Co0.7Fe0.3O2.85 (LnSCCF, Ln=La, Pr and Nd; abbreviated as L-72173, P-72173 and N-72173) were synthesized by microwave sintering (MWS) techniques. The formation process, phase structure and composition were characterized using TG/DTA, XRD and EDS. The thermal expansion behavior of the samples was analyzed in the range of 20-950 °C by thermal dilatometer. The electrical conductivity of the samples was measured with DC four-terminal method from 25 to 900 °C. The X-ray diffraction shows that the samples exhibit a single phase with rhombohedral or cubic perovskite structure after sintered at 1200 °C for 20 min. The electrical conductivity of the samples increases with temperature up to a maximum, and then decreases gradually at higher temperature owing to the creation of oxygen vacancies. The small polaron hopping is regarded as the conducting mechanism (T 550 °C). L-72173 has higher mixed conductivity ( >300 S·cm-1) in 550-800 °C. The average TECs of L-72173, P-72173 and N-72173 are 1.389× 10-5 K-1, 1.417 × 10-5 K-1 and 1.416 × 10-5 K-1 in the range of 25-800 °C, respectively. They are thermally matched to the GDC better than the YSZ and SDC.

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59-62

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September 2013

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© 2013 Trans Tech Publications Ltd. All Rights Reserved

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[1] F Sun, Y Zheng, X L Gao, et al: Metallic Functional Materials Vol. 17(2010), p.75.

Google Scholar

[2] D J L Brett, A Atkinson, N P Brandon, et al: Chemical Society Reviews Vol. 37(2008), p.1568.

Google Scholar

[3] Z. P Shao: Progress in Chemistry Vol. 23(2011), p.418.

Google Scholar

[4] C W Sun, R Hui, J Roller: Journal of Solid State Electrochemistry, Vol. 14(2010), p.1125.

Google Scholar

[5] J H Kim, H Kim: Ceramics International, Vol. 38(2012), p.4669.

Google Scholar

[6] T Ebadzadeh, M Valefi: J. Alloys Compd. 448(2008), p.246.

Google Scholar

[7] R H Liu, W H Ma: Rare Metals Vol. 31(2007), p.86.

Google Scholar

[8] C F Zhu, G Wang, J H Xue, et al: Acta Physico-Chimica Sinica Vol. 25(2009), p.1179.

Google Scholar