Development of Solid Oxide Electrolysis Cells for Hydrogen Production at High Current Densities

Abstract

An ongoing challenge for solid oxide electrolysis cells (SOECs) operated at high current densities, is the considerable long-term degradation of the most commonly used Ni/yttria-stabilized zirconia (YSZ) H2-electrode. In this work, we report a scalable route of infiltrating nano-sized electrocatalysts into the Ni/YSZ electrode of the cell after it has been reduced in a “one-atmosphere-reduction” process to address this challenge. The performance and durability of an infiltrated cell and a non-infiltrated sister-cell are evaluated. The infiltrated cell exhibits significantly enhanced long-term durability at high current densities, with cell voltage degradation rates of 0.028 V kh-1 (2.04 % kh-1) at −1.25 A cm-2 and 0.010 V kh-1 (0.78 % kh-1) at −1.00 A cm-2. These degradation rates are ∼14 times and ∼25 times less than those of the non-infiltrated cell, respectively.