| 학회 | 한국재료학회 |
| 학술대회 | 2011년 봄 (05/26 ~ 05/27, 제주 휘닉스 아일랜드) |
| 권호 | 17권 1호 |
| 발표분야 | C. Energy and the Environment Technology(에너지 및 환경재료) |
| 제목 | Development of cobalt-free LaxSr4-xFe6O13 (0 ≤ x≤ 2) Intergrowth Cathode Material for Solid Oxide Fuel Cells |
| 초록 | Cobalt-free LaxSr4-xFe6O13 (0 ≤x≤ 2) oxide have been synthesized and investigated as a potential cathode material for solid oxide fuel cells (SOFCs). Sr4Fe6O13 consists of alternating perovskite layers (Sr4Fe2O8) containing iron cations in octahedral oxygen coordination and Fe4O5 layers where iron cations have 5-fold coordination of two types-square pyramids and trigonal bipyramids. Our preliminary electrochemical testes of pristine Sr4Fe6O13 show a rather high area specific resistance (0.47 Ω cm2 at 700 oC) for ~20 μm thick layers with CGO electrolyte. The electrochemical performances are improved by La addition up to x=1 (La1Sr3Fe6O13, 0.06 Ω cm2 at 700 oC). In addition, thermal expansion coefficient (TEC) values of La1Sr3Fe6O13 specimen demonstrated 15.1 x 10-6 oC-1 in the range of 25-900 oC, which provides good thermal expansion compatibility with the CGO electrolyte. An electrolyte supported (300-μm-thick) single-cell configuration of La1Sr3Fe6O13/CGO/Ni-CGO delivered a maximum power density of 584 mWcm-2 at 700 oC. In addition, an anode supported single cell by YSZ electrolyte (10-μm-thick) with a porous CGO interlayer between the cathode and the electrolyte to avoid undesired interfacial reactions exhibited 1517 mWcm-2 at 800 oC. The unique composition of La1Sr3Fe6O13 with low thermal expansion coefficient and higher electrochemical properties could be a good cathode candidate for intermediate temperature SOFCs with CGO and YSZ electrolyte. |
| 저자 | 이승준1, 용석민1, 김동석1, 김도경2 |
| 소속 | 1KAIST, 2교수 |
| 키워드 | Solid oxide fuel cells; cathode; electrochenical properties |
