Relationship between fabrication method and chemical stability of Ni-BaZr0.8Y0.2O3-δ membrane

JOURNAL OF POWER SOURCES

卷:278

Article

Fang, Shumin¹  Wang, Siwei²  Brinkman, Kyle S.²  Su, Qing³  Wang, Haiyan³  Chen, Fanglin¹ 

[1] Univ S Carolina, Dept Mech Engn, Columbia, SC 29208 USA

[2] Clemson Univ, Dept Mat Sci & Engn, Clemson, SC 29634 USA

[3] Texas A&M Univ, Mat Sci & Engn Program, College Stn, TX 77843 USA

关键词: Hydrogen permeation;    Composite membrane;    High temperature proton conductor;    Barium zirconate;    Chemical stability;   

DOI  :  10.1016/j.jpowsour.2014.12.108

来源: Elsevier

【 摘 要 】

NiO effectively promotes the sintering of highly refractory Y-doped BaZrO3 (BZY) through the formation of BaY2NiO5, providing a simple and cost-effective method for the fabrication of dense BZY electrolyte and Ni-BZY hydrogen separation membrane at similar to 1400 degrees C. Unfortunately, insulating BaCO3 and Y2O3 phases formed on the surface of BZY and Ni-BZY prepared by solid state reaction method with NiO after annealing in wet CO2. Ni-BZY membranes prepared from different methods suffered different degree of performance loss in wet H-2 at 900 degrees C. The chemical instability of Ni-BZY is attributed to the formation of a secondary phase (BaY2O4) generated from the reduction of BaY2NiO5 in Hy during the sintering process. Both BaY2O4 and BaY2NiO5 react with H2O, and CO2 at elevated temperatures, generating insulating Ba(OH)(2) and BaCO3 phases, respectively. The less BaY2O4 is formed in the fabrication process, the better chemical stability the Ni BZY membranes possess. Therefore, a new Ni BZY membrane is prepared through a judicial combination of BZY powders prepared from combined EDTA-citric and solid state reaction methods, and demonstrates exceptional chemical stability in H2O and CO2, enabling stable and even improved hydrogen flux in wt 50% CO2 at 900 degrees C. (C) 2014 Elsevier B.V. All rights reserved.

【 授权许可】

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