Performance and Durability of Reversible Solid Oxide Cells with Nano-electrocatalysts Infiltrated Electrodes

This work focuses on improving the durability of Ni/yttria-stabilized zirconia (YSZ) fuel electrode-supported solid oxide cells under the reversible operation mode by infiltrating nano-sized electrocatalysts into both electrodes. The resulting cell consists of a CGO (Gd-doped CeO2) scaffold-based oxygen electrode that is infiltrated with LSC (La0.6Sr0.4CoO3-δ) and CGPO (Gd, Pr-co-doped CeO2) nanocomposite infiltrates and a Ni/YSZ fuel electrode modified with nano-CGO infiltrates. Constant-current tests at + 0.5 A/cm2and − 0.5 A/cm2are carried out, followed by cycling between fuel-cell and electrolysis modes at ± 0.5 A/cm2and ± 1.25 A/cm2. Under the reversible operation at ± 0.5 A/cm2, the cell showed lower degradation rates than under the single mode operation, with cell voltage degradation of 1.23%/kh in fuel cell mode and 0.53%/kh in electrolysis mode. During the cycling operation at ± 1.25 A/cm2, the overall degradation rate under the electrolysis mode was only 0.46%/kh. Compared to the previously tested cells with only LSC infiltrated oxygen electrodes, the cell tested in this work shows better durability with degradation rates of less than half of the previous tests. The results in this work demonstrate that infiltrating nano-electrocatalysts into both electrodes is an effective solution to boost cell performance and durability under reversible operation.