| 학회 | 한국화학공학회 |
| 학술대회 | 2015년 봄 (04/22 ~ 04/24, 제주 ICC) |
| 권호 | 21권 1호, p.912 |
| 발표분야 | 재료 |
| 제목 | First-principles calculations of thermodynamic driving force for cation segregation on perovskite-type materials |
| 초록 | Cation segregation leads to various product phases at the surfaces and interfaces of solid oxide fuel cell (SOFC) cathodes. It has the direct relations to control the oxygen reduction reaction and stability of SOFC cathode. Therefore, identifying the thermodynamic driving force for cation segregation plays an important role in designing high performance SOFC cathodes. In this study, we investigated the thermodynamic behavior of cation segregation in two classes of perovskite-type materials using density DFT calculations. The first class is alkaline earth metal (Ba, Sr, and Ca)-doped LaBO3 (B = Cr0.50Mn0.50, Mn, Fe, Co0.25Fe0.75, Co, and Ni) perovskites and the second class is SrTi1-xFexO3 (x = 0.00, 0.25, 0.50, 0.75, 1.00) perovskites. While the dopant segregation (Ba, Sr, and Ca) is observed in the first class, lattice cation (Sr) segregation is observed in the second class. Although there are two different mechanisms in cation segregation, the mainly driving force is similar for both cases. We found that the strain effect induced size difference of A-site and B-site cations in perovskite oxides is the most dominant driving force. |
| 저자 | 권형욱1, 한정우1, 이원영2, 정우철3 |
| 소속 | 1서울시립대, 2성균관대, 3카이스트 |
| 키워드 | segregation; SOFC; DFT |
| 원문파일 | 초록 보기 |
