Fabrication of a strontium-doped lanthanum chromite (LSC) thin film on SUS430 substrate for carbon coking protecting layer of direct hydrocarbon solid oxide fuel cells

초록

A thin strontium doped lanthanum chromite (La0.8Sr0.2CrO3, LSC) layer to protect a stainless steel interconnector of solid oxide fuel cell from carbon deposition was coated by dipping technique from the precursor solution of La, Sr, Cr nitrates, acetylacetone (AcAc), and 2-methoxyethanol. The effect of AcAc on phase behavior and microstructure evolution of LSC thin films was investigated. The thin film heat-treated at 800°C in air consisted of perovskite LaCrO3, Mn1.5Cr1.5O4, and Cr2O3 phases. The addition of a chelating agent, AcAc to the precursor solution could lead to reduce the formation of an strontium chromite (SrCrO4) phase, which resulting in dense microstructure of the thin film. It was confirmed by FT Raman spectroscopic analysis and FESEM observations that the carbon deposited on an uncoated SUS430 substrate was amorphous with spherical morphology. The obtained LSC thin film was found to be very effective on preventing carbon deposition under dry hydrocarbon atmosphere.