| 초록 |
Perovskite type materials offer excellent oxidation, sulfidation and carburization resistances; stability in terms of dimension, microstructure, chemistry and phase; high electronic and thermal conductivity; comparable coefficient of thermal expansion to the solid electrolytes. Therefore, they have widely been applied as cathode, anode, ceramic coating material in current-collectors and inter-connectors in intermediate temperature solid oxide fuel cells (IT-SOFCs). LaCrO3, the best inter-connecting and current collecting material, offers the cited properties except the low electronic conductivity (~0.34 S/cm at 700℃). The present paper reports synthesis of novel Perovskites: (La1-xSrx)(Cr0.85Co0.05Fe0.05Ni0.05)O3 (x = 0.1 – 0.4 in mole fraction) using metal nitrates by Sol-Gel method. The samples were characterized using X-ray diffractometry (XRD), Pycnometry and Fourier-Transform Infra-red spectroscopy (FT-IR). MAUD (a Rietveld program) was applied to understand the structural change with composition. The samples were Perovskite in nature with Rhombohedral (space group: R-3c) structure. An increase in x resulted in a decrease in cell volume and cell density following the trend of measured density. The average crystallite size, calculated by Scherrer formula at 2Θ = 32.5°, was also decreased from 44.6 to 29 nm. The results were found well correlated with FT-IR study. |
