“…During the past, Cobalt containing oxides of different composition, such as Ln 1 À x Sr x Co 1 À y Fe y O 3 À δ (Ln=rare-earth) [8][9][10][11][12], Ba 1 À x Sr x Co 1 À y Fe y O 3 À δ [5,[13][14][15][16], LnBaCo 2 O 5 þ δ (Ln=rare-earth) [17][18][19][20][21], and RBa(Co, M) 4 O 7 (R=Y, Ca, In and M=Zn, Ga, Al) [22][23][24][25][26][27], have been extensively exploited as potential cathode materials for IT-SOFCs, owing to their excellent electrocatalytic activity for the oxygen reduction reaction (ORR). However, most of these materials usually show poor chemical stability, insufficient chemical compatibility with the electrolyte, high thermal expansion coefficient, high cost of cobalt element and easy evaporation.…”