Processing of graded anode-supported micro-tubular SOFCs based on samaria-doped ceria via gel-casting and spray-coating

作者：Morales M^*; Navarro M E; Capdevila X G; Roa J J; Segarra M

来源：Ceramics International, 2012, 38(5): 3713-3722.

DOI：10.1016/j.ceramint.2012.01.015

• SOFC
• Micro-tubular SOFC
• Graded anode
• Doped ceria
• Gel-casting
• Spray-coating

A simple gel-casting method was successfully combined with the spray-coating technique to manufacture graded anode-supported microtubular solid oxide fuel cells (MT-SOFCs) based on samaria-doped ceria (SDC) as an electrolyte. Micro-tubular anodes were shaped by a gelcasting method based on a new and simple forming technique that operates as a syringe. The aqueous slurry formulation of the NiO-SDC substrate using agarose as a gelling agent, and the effect of spray-coating parameters used to deposit the anode functional layers (AFLs) and electrolyte were investigated. Furthermore, pre-sintering temperature of anode substrates was systematically studied to avoid the anode electrolyte delamination and obtain a dense electrolyte without cracks, after co-sintering process at 1450 degrees C. Despite the high shrinkage of substrate (similar to 70%), an anode porosity of similar to 37% was achieved. MT-SOFCs with similar to 2.5 mm of outer diameter, 370 mu m thick substrate, 20 mu m thick AFLs and 15 mu m thick electrolyte were successfully obtained. The use of AFLs with 30:70 and 50:50 wt% NiO-SDC allowed to obtain a continuous gradation of composition and porosity in the anode-electrolyte interface.

• 出版日期2012-7