Suppression of multiple magnetic ordering induced by Nb and Ru substitution in SrCoO3-δ systems

Investigation of the Role of Sr and Development of Superior Sr-Doped Hexagonal BaCoO3−δ Perovskite Bifunctional OER/ORR Catalysts in Alkaline Media

“…Sr is known to stabilize the high spin Co 3+/4+ ions in the perovskite structure. Similarly, the existence of high spin Co 3+ (t 2 g 5 eg 1 ) and/or Co 4+ (t 2 g 4 eg 1 ) in the perovskite lattice is known to enhance the electrocatalytic activity for both ORR and OER. , A model of such an active electrocatalyst oxide surface is established; in the oxygen-vacant BO 5 octahedra containing surface oxygen vacancies, the 3d orbital (e g and t 2g ) energy split further due to a lower symmetry near the surface, resulting in more active sites for reaction along the (011) planes of Ba 0.5 Sr 0.5 CoO 3−δ -type oxygen-vacant perovskite…”

Perovskite La1−xKxCoO3−δ (0 ≤ x ≤ 0.5): a novel bifunctional OER/ORR electrocatalyst and supercapacitive charge storage electrode in a neutral Na2SO4 electrolyte

“…Similarly, the existence of intermediate spin Co 3+ (t 5 2g e 1 g ) and/or Co 4+ (t 4 2g e 1 g ) in the perovskite lattice is known to lead to enhanced electrocatalytic activity toward OER and ORR. 39,40,48–53 Fig. 4(b) shows double-exchange Co 3+ –O 2− –Co 4+ interaction in the La 1− x K x CoO 3− δ (0 ≤ x ≤ 0.5) samples.…”

“…The presence of Co 3+ and Co 4+ in the oxygen vacant La 1− x K x CoO 3− δ perovskite sample can enhance the catalytic OER/ORR activity due to the participation of active metal redox (Co 3+/4+ ) and the existence of intermediate spin Co 3+ (t 5 2g e 1 g ) and/or Co 4+ (t 4 2g e 1 g ) and the oxygen vacant BO 5 octahedra in the perovskite lattice that further split the 3d orbital (e g and t 2g ) due to lower symmetry near the surface creating more active surface sites for the superior OER/ORR activity. 39,51…”

“…5 ) and the oxygen vacant BO 5 octahedra in the perovskite lattice that further split the 3d orbital (e g and t 2g ) due to lower symmetry near the surface creating more active surface sites for the superior OER/ORR activity. 39,51 Fig. 6(a) shows a comparative study of OER performances of La 0.7 K 0.3 CoO 3Àd , Ba 0.5 Sr 0.5 CoO 3Àd , 40 and BSCF (Ba 0.5 Sr 0.5 -Co 0.8 Fe 0.2 O 3Àd ), 37 with BSCF being a well-known model electrocatalyst for OER.…”

Multiple-phase evolution and electrical transport of Sr4−xYxCo4O12−δ (x = 0–1.0): an ordered phase transition process

“…[1][2][3][4][5][6][7] Research on the multiple-phase structure evolution and controllable synthesis of ceramics based on cobalt oxides will provide a deeper scientific understanding and application value of this material family. [7][8][9][10][11][12][13][14][15][16] SrCoO 3−δ , a well-known phase transition material, has an orthorhombic brownmillerite (OB) structure at room temperature, which can become a hexagonal (H) structure at 653 °C and a cubic perovskite (CP) structure at 920 °C. 17 After cooling to 774 °C, it can revert to the H structure and maintain this structure down to room temperature.…”