“…Some other double-perovskite electrode materials also show good cell performances, such as Ba 2 CoMo 0.5 Nb 0.5 O 6−delta [16], Sr 2 FeMoO 6 [17,18], YBaCo 2−x Fe x O 5+delta [19], SmBaCuCoO 5+delta [20], etc [21][22][23][24]. Moreover, we have introduced Sr 2 FeNbO 6 to SOEC and proved that it can be used as the hydrogen electrode and its electrochemical performance is better than that of Ni under the same operation conditions [25].…”