Fabrication and performance of solid oxide electrolysis cells with sputtered thin film ceria barrier layers

The feasibility of fabricating gadolinia-doped ceria (GDC) thin films as barrier layers for solid oxide electrolysis cells (SOECs) was investigated using sputtering with an unbalanced magnetron cathode. Structural and chemical analyses confirmed the formation of dense, well-crystallized GDC films with uniform adhesion to the electrolyte. The Ni-YSZ electrode-supported SOECs with sputtered GDC barriers were tested at 750 °C, and their performance was compared to that of SOECs with a screen-printed GDC barrier. The ohmic resistance was significantly reduced when using thin film GDC. The ability to deposit GDC films with relatively uniform thickness across a 15 cm × 15 cm area was demonstrated, suggesting excellent potential for scalability. The sputtered GDC films exhibited robustness and durability withstanding 1000 h of operation under accelerated stress conditions, including voltages above thermoneutral and high current densities of 1.2–1.5 A/cm 2 , without any evidence of Sr migration or film degradation. • Sputtering method eliminates one high-temperature fabrication step. • Dense thin film GDC served as effective barrier mitigating Sr migration. • Thin film GDC withstood accelerated stress testing at high currents. • Cell ohmic resistance was reduced by 50 % compared to screen-printed barriers. • Sputtering method is scalable to fabricate large-area solid oxide cells.