Engineering a high-performance W-doped Sr0.9Fe0.67Ti0.3Co0.03O3-δ hydrogen electrode for solid oxide electrolysis cells

Traditionally, Ni-based cermet fuel electrodes have been extensively utilized in solid oxide electrolysis cells (SOECs) owing to their excellent conductivity and electrochemical catalytic activity. However, the development of alternative materials has gained attention due to concerns over Ni's susceptibility to carbon deposition and long-term stability issues. In the present study, we design W-doped Sr 0.9 Fe 0.67 Ti 0.3-x Co 0.03 O 3-δ (SFTCW, x = 0.01) as a novel hydrogen electrode material for SOECs. The results reveal that W doping promotes the precipitation of bimetallic Co-Fe alloy, thereby increasing the active sites within the material and preserves the original structure. In a reducing atmosphere, SFTCW demonstrates superior performance compared to SFTC in both Sc 2 O 3 stabilized ZrO 2-δ (ScSZ) and La 0.8 Sr 0.2 Ga 0.8 Mg 0.2 O 3-δ (LSGM)-electrolyte supported cells. LSGM-based cells exhibit superior performance, 5 times higher than ScSZ-based cells, achieving an electrolysis current density of ∼1000 mA cm −2 and demonstrating considerable stability for up to 122 h, indicating the potential application of SFTCW for solid oxide electrolysis cells.