Study of solid oxide electrolysis cells operated in potentiostatic mode: Effect of operating temperature on durability

Potentiostatic operation of solid oxide electrolysis cells (SOECs) at the thermoneutral voltage enables SOECs close to 100% electrical efficiency and simplifies heat management stack system level. In this work, we investigate long-term durability Ni/yttria-stabilized zirconia (YSZ) fuel electrode supported operated for steam 1290 mV, by testing 800, 750, 700 ? periods exceeding 1000 h each. The show different initial performance due operating temperatures, but all experience a significant degree degradation within first 300 h, with rate 2.80, 1.93, 1.77 A cm?2 kh?1 (~1.80, 1.51 1.90% kh?1) tested ?, respectively. Hereafter stable or even slight activation. After operation, cell 750 exhibits comparable 800 more than 74% higher is maintained until end test, suggesting that among three temperatures optimum one. behavior further investigated electrochemical impedance spectroscopy (EIS) analysis post-test microstructural characterization. cause discussed in terms overpotential. Our findings highlight significance temperature optimization on when potentiostatic mode.