Rational design of YSZ trilayer-structured solid oxide cells for power generation and hydrogen production

Solid oxide cells (SOCs) hold great promise for efficient power generation and hydrogen production, with performance strongly influenced by cell architecture. Herein, we present a rational design of yttria-stabilized zirconia (YSZ) trilayer-structured SOCs, combining porous|dense|porous scaffold engineered with optimized catalyst impregnation techniques. Symmetrical cell analyses reveal that the pore structure of the porous scaffold governs the optimal catalyst loading, while scaffold thickness is critical for minimizing gas diffusion resistance. Sequential impregnation of Ce_0.9Gd_0.1O_2-δ (CGO) and La_0.6Sr_0.4CoO_3-δ (LSC) into the YSZ scaffold produces air electrodes with polarization resistances as low as 0.009 Ω cm² at 850 °C and 0.025 Ω cm² at 750 °C. During steam electrolysis, the electrolyte-supported single cells achieve stable operation for 160 h under high current densities of −0.75 A cm⁻² and −1.00 A cm⁻². These results highlight the potential of trilayer-structure fabrication and catalyst impregnation as effective strategies for advancing the SOC technology.