| 초록 |
Perovskite type ceramic oxides exhibit unique properties, namely, excellent oxidation, sulfidation and carburization resistances; stability in terms of dimension, microstructure, chemistry and phase; high electronic and thermal conductivity; and coefficient of thermal expansion comparable to the solid electrolytes. Therefore, it has been widely applied as cathodes for the Solid Oxide Fuel Cells (SOFCs). It have also been applying as coating materials to coat on metals/ polymer template in order to use as current-collectors and inter-connectors in the SOFCs. LaCrO3 offers the cited properties except the low electronic conductivity (~0.34 S/cm at 700℃). The present paper reports XRD analysis of novel cathode: (La0.9Sr0.1)(Cr0.85Co0.05Fe0.05Ni0.05)O3. The samples in powder form were synthesized using two different groups of starting precursors: metal acetates and metal nitrates by Sol-Gel method. Various routes (#A-F) of the Sol-Gel method were used for controlling the hydrolysis-condensation reaction. The X-ray diffractometry (XRD) confirmed the formation of single Perovskite phase of Orthorhombic structure. The average crystallite size (19 – 40 nm) of the Perovskite phase was calculated by Scherrer formula at the strongest peak, 2Θ = 32.5°. The structural parameters: a, b, c; cell volume and density were calculated using the method of Holland & Redfern (1995) as well as MAUD (Rietveld program) and found comparable to those of LaCrO3 (JCPDS: 83-1327). |
