| 초록 |
Single chamber solid oxide fuel cell (SOFC) of micro-patterned electrode structures on the same electrolyte surface has been fabricated by microfluidic lithography. Flexible polymeric mold with a surface relief structure was prepared by replicating against SU-8 photoresist master with poly(dimethylsiloxane) (PDMS). Micro-channels formed by contacting the mold with a substrate of samarium doped ceria (SDC) were simultaneously filled with two well-dispersed slurries of NiO-GDC-Pd cermet anode and LSCF (La0.8Sr0.2Co0.2Fe0.8O3) cathode materials by vacuum-assisted infiltration. The slurries were solidified upon solvent evaporation through PDMS mold, resulting in the cross-inserted comb-type single chamber SOFC in an area of 5ⅹ5 mm2 in which each electrode had 100 μm linewidth with varying anode-to-cathode distances 50, 75 and 100 μm. After the PDMS was demolded, the green body was co-fired at 1100 °C for 2 hours with a ramping rate of 2 °C/min. Finally three kind of SOFCs which has different gap between electrodes were fabricated. The sintered electrode structure was observed with scanning electron microscopy (SEM) and surface profilometer. Electrochemical property and I-V characteristics of the SOFC were measured using a methane-air mixture by impedance analyzer and DC source measure unit under the various condition of gas flow, gas composition and the geometry of the cell. |
