Preparation of bulk-like La0.8Sr0.2Ga0.8Mg0.2O3-δ coatings for porous metal-supported solid oxide fuel cells via plasma spraying at increased particle temperatures.

While porous metal-supported solid fuel oxide cells (PMS-SOFCs) have the potential to decrease the cost and increase the start-up speed of power units, the available fabrication processes remain too cumbersome for industrial production. In this study, we prepared bulk-like strontium and magnesium-doped lanthanum gallate (LSGM) coatings using atmospheric plasma spraying (APS) at an increased particle temperature. The large equiaxed grains inside the coatings indicated the epitaxial growth of the splat interfaces and improvement in the coating quality. With increased particle temperature, the conductivity of dense LSGM coatings directly deposited by APS was comparable to that of the bulk material, and cell performance was also significantly enhanced. The maximum power density of the PMS-SOFC at 700 °C was 831 mW cm−2 and 596 mW cm−2 when high and low particle temperatures were used, respectively. These results indicated that the quality of the coating was improved by increasing the in-flight particle temperature. [Display omitted] • LSGM coatings become very dense benefited from the increased particle temperature. • The densification mechanism is from the epitaxial growth of the interfaces. • The conductivity of the LSGM coating is comparable to the bulk from sintering. • The MPD reaches 831 mW cm−2 at 700 °C based on the increased particle temperature. [ABSTRACT FROM AUTHOR]