Poisoning of Solid Oxide Electrolysis Cells by Impurities

Electrolysis of H 2 O, CO 2 , and co-electrolysis of H 2 O and CO 2 was studied in Ni/yttria-stabilized zirconia YSZ electrode supported solid oxide electrolysis cells SOECs consisting of a Ni/YSZ support, a Ni/YSZ electrode layer, a YSZ electrolyte, and an lanthanum strontium manganite LSM/YSZ oxygen electrode When applying the gases as received, the cells degraded significantly at the Ni/YSZ electrode, whereas only minor and initial degradation was observed for either the Ni/YSZ or LSM/YSZ electrode. Application of clean gases to the Ni/YSZ electrode resulted in operation without any long-term degradation, in fact some cells activated slightly. This shows that the durability of these SOECs is heavily influenced by impurities in the inlet gases. Cleaning the inlet gases to the Ni/YSZ electrode may be a solution for operating these Ni/YSZ-based SOECs without long-term degradation.