Powder and Electrical Properties of La_0.6Sr_0.4CoO_3-δ Cathode Material Prepared by a Modified Sol- Gel Method for Solid Oxide Fuel Cell Application

The powder properties and electrical conductivity of lanthanum strontium cobalt oxide, la_0.6sr_0.4co_o3-δ (lsc) material were systematically characterized with respect to application as cathode material for intermediate temperature solid oxide fuel cell (sofc). the lsc was prepared via a modified sol-gel method assisted with a combination of ethylene glycol and activated carbon as a chemical additive. the decomposition of impurity compounds such carbon compounds and nitrates in the precursor powder was completed at 870°c as revealed by thermogravimetry (tg) analysis. as the calcination temperature increased from 800°c to 1000°c, the purity and crystallite size of the the calcined precursor powder also increased as confirmed by x-ray diffrcation (xdr) analysis. the micrograph of scanning electron microscope (sem) image showed that the particle of the calcined powders form agglomeration and this led to low relative density (80.18%) of the sintered lsc pellet at 1200°c. the direct current electrical conductivities (σdc) of the sintered lsc pellet measured using van der pauw technique in air were 1504 s cm^-1 and 1069 s cm^-1 at 400°c and 800°c, respectively. the relatively high σdc with low activation energy (ea) of 0.021 ev indicates that the lsc prepared in this work has a great potential to be used as a cathode material for intermediate temperature sofc application.