Ni-alloy fuel electrodes for reversible solid oxide cells

Reversible solid oxide cells (r-SOCs) are devices that can operate efficiently in both fuel cell and electrolysis operation modes. Nickel is widely used as an anode in conventional solid oxide fuel cells (SOFCs), but this agglomerates due to redox cycling, leading to irreversible performance degradation, making it unsuitable for r-SOCs. Here, we apply alternative electrodes to r-SOCs, in which Ni-Co alloy functions as a catalyst and an electronic conductor, whilst Ce0.9Gd0.1O2 (GDC) functions as a mixed ionic-electronic conductor. The electrochemical performance of these Ni-Co-GDC electrodes and their reverse-operation durability in r-SOCs are evaluated, and the effect of varying the amount of Co is investigated, compared with conventional cermet fuel electrodes. These novel materials exhibit high electrochemical performance and durability against SOFC/SOEC reverse-operation cycling.