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This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. containing either a thin PL porous layer (40 µm), and/or a DS dense membrane (500 µm), and/or a PS porous substrate (500 µm). Activated carbon (i.e. porogen agent) at 20 wt% was mixed with BSCF to form porous structures. The membranes were processed by dry pressing followed by sintering at high temperatures. The best oxygen fluxes of 2.86 mL min -1 cm -2 at 850 °C were achieved with the PL-DS membrane configuration, which delivered a 42% higher oxygen flux than the DS dense membrane. This improvement was attributed to the larger contact area with the air feed conferred by the thin PL porous layer. However, the PL-DS-PS configuration resulted in a 21% decrease of oxygen flux as compared to the PL-DS membrane which strongly suggested that the PS porous substrate contributed extra resistance to the transport of oxygen. CT scan analysis of the PS porous substrate revealed that the pore volume was concentrated in the center of the PS porous substrate, with a reduced pore volume contribution closer to the external surface. 3D 2 analysis revealed the connectivity of the regions closer to the external surface was over three orders of magnitude lower than that of the center of the PS porous substrate, thus creating a bottle-neck.Although all pores were large (> 1 µm), the expected resistance should be very low, however, the bottle-neck region closer to the external surface provided additional resistance for the transport of oxygen from the membrane interface to the permeate side.

The fabrication of mixed ionic-electronic conducting (MIEC) ceramic-based membranes for oxygen separation has extensively increased in the last three decades as a promising alternative of clean energy delivery. In recent years, the interest on supported MIEC membranes has increased due to their attractive properties such as higher mechanical strength and oxygen flux compared to selfsupported membranes. This work presents a literature review on the development of supported MIEC membranes of perovskite structure. The concepts and transport mechanism of those membranes are explained and recent works on supported MIEC membranes are presented. Finally, manufacturing methods of self-supported membranes and their influence on oxygen permeation are discussed.

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LZSA glass ceramic (LiO2-ZrO2-SiO2-Al2O3) was tested for its thermomechanical compatibility as a sealing material with a stainless steel interconnect (AISI 430) of a planar SOFC. With this purpose, the densification and crystallization behavior of LZSA were investigated initially. It was observed that the material reached maximum relative density and shrinkage, respectively 95% and 17%, at 800°C, which corresponded approximately to the crystallization temperature of the material as evidenced by DTA analysis. In the next step, LZSA tapes were cast from slurries and prepared either as LZSA laminates or LZSA-steel bilayers. The densification behavior and microstructural features of cofired LZSA laminates and LZSA-steel bilayers were analyzed at 800 and 900°C. Maximum relative density and defect-free interfaces were observed for laminates and bi-layers cofired at 800°C, whereas increased porosity and detached bi-layer were the characteristics of the samples fired at 900°C.