Preparation and characterization of La _(0.9)Sr _(0.1)Ga _(0.8)Mg _(0.2)O _(3-δ) thin film electrolyte deposited by RF magnetron sputtering on the porous anode support for IT-SOFC

摘要

Thin films of solid electrolyte La _(0.9)Sr _(0.1)Ga _(0.8)Mg _(0.2)O _(3-δ) (LSGM) were deposited by RF magnetron sputtering onto porous La _(0.7)Sr _(0.3)Cr _(0.5)Mn 0.5O _(3-δ) (LSCM) anode substrates. The effects of substrate temperature, sputtering power density and sputtering Ar gas pressure on the LSGM thin film density, flatness and morphology were systematically investigated. RF sputtering power density of 7.8 W cm ~(-2), substrate temperature of 300°C and sputtering Ar gas pressure of 5 Pa are identified as the best technical parameters. In addition, a three-electrode half cell configuration was selected to investigate the electrochemical performance of the thin film. The LSGM film deposited at optimum conditions exhibited a lower area specific ohmic resistance of 0.68 Ω cm ~(-2) at 800°C, showing that the practicability of RF magnetron sputtering method to fabricate LSGM electrolyte thin film on porous LSCM anode substrates.