Solid oxide electrolyzer positive electrodes with a novel microstructure show unprecedented stability at high current densities

Abstract

Solid oxide electrolysis cells (SOECs) have captured worldwide attention as a promising energy conversion device, but durability at large current densities is still an issue. Here, the authors present an encouraging stable anode design for electrolysis at high current densities, in which a nano La_0.6Sr_0.4CoO_3−δ (LSC) catalyst network is integrated with robust microchannels of the yttria-stabilized zirconia scaffold. Such a controlled structured electrode not only allows rapid gas diffusion, but also provides sufficient active sites as well as firm anode–electrolyte interface adhesion for achieving highly stable and efficient electrolysis. These unique advantages lead to an extremely low polarization resistance of 0.010 Ω cm² and high durability for over 100 h at a large current density of 3.4 A cm⁻² at 800 °C. The outstanding performance demonstrates that the as-prepared cell structure may be generally applicable in the design of high-efficiency energy conversion systems.