A Novel Solid Oxide Electrolysis Cell with Micro‐/Nano Channel Anode for Electrolysis at Ultra‐High Current Density over 5 A cm⁻²

Abstract Solid oxide electrolysis cells (SOECs) are regarded as promising candidates for the next generation of energy conversion device due to their extremely high conversion efficiency. However, the electrolysis current density should be further increased to meet the demands of large‐scale industrial application in the future. Here, a novel anode configuration for SOEC is reported that achieves an ultra‐high current density of 5.73 A cm⁻² for at least 4 h. To the best of the authors’ knowledge, such current density surpasses the record of present state‐of‐the‐art research. The unique stability under such high current density is attributed to the novel SOEC constructed with a La_0.6Sr_0.4CoO_3−δ anode catalyst nano‐layer to promote oxygen generation, vertically aligned micro channel anode scaffold to accelerate oxygen release, and integrated anode–electrolyte interface to improve the interfacial strength. The novel SOEC successfully demonstrates stable steam electrolysis under an ultra‐high current density of 5.96 A cm⁻² at 800 °C under the constant operating voltage of 1.3 V, corresponding to a hydrogen production rate of 2.5 L h⁻¹ cm⁻².