| 학회 | 한국재료학회 |
| 학술대회 | 2012년 가을 (11/07 ~ 11/09, 라카이샌드파인 리조트) |
| 권호 | 18권 2호 |
| 발표분야 | C. 에너지/환경 재료(Energy and Environmental Materials) |
| 제목 | Synthesis and characterization of core-shell structured Ni@YSZ using ultrasonic pyrolysis process for solid oxide fuel cell anodes |
| 초록 | Solid oxide fuel cells (SOFCs) are promising energy conversion systems due to their high energy converting ability. In addition, hydrocarbon fuel can be used without external reforming process due to their high operating temperature. Main reaction at the SOFC anode is the oxidation of a fuel, which creates electric charges and delivers them to the cathode through the external circuit. Nickel provides high catalytic activity for the oxidation of hydrogen gases to hydrogen ions. Usually, nickel is used with electrolyte materials such as yttria stabilized zirconia (YSZ), which is ceramic metal composite (cermet). YSZ in Ni-YSZ cermet can reduce the thermal expansion mismatch with electrolyte and provide ionic conductivity. Anode reaction occurs at the triple-phase boundary (TPB) of gas, anode catalyst and electrolyte. Although Ni-YSZ is conventional anode materials, there is degradation in the anode side during long-term operation at high temperature, such as nickel aggregation leading to a decrease in the reaction sites. Core-shell structure can be one of the ways to avoid the nickel aggregation. In this study, we synthesized core-shell structured Ni@YSZ anode powders using an ultrasonic pyrolysis process with the 3-zone furnace. The multi-zone furnace can control the heat treatment temperature and lead to separate the decomposition temperature of the precursors. As-synthesized nickel powders were completely covered by nano-scaled YSZ particles and the core-shell structure restrained the grain growth. Morphology of the as-synthesized powders was studied with SEM. We also used TEM and EDS line scanning to confirm the core-shell structure. Phase analysis for the as-synthesized powders was carried out by XRD. Finally, the electro-chemical performances of the single cells with the Ni@YSZ anodes were evaluated by AC impedance spectroscopy and I-V measurement. |
| 저자 | Chaehyun Lim1, Ki-Tae Lee2 |
| 소속 | 1Division of Advanced Materials Engineering, 2Chonbuk National Univ. |
| 키워드 | SOFC; core-shell; USP |
