摘要
Cubic perovskite oxides usually suffer from delamination and Sr^(2+) segregation for catalyzing oxygen evolution reaction (OER) at the anodes of solid oxide electrolysis cells (SOECs). It is crucial to develop alternative and efficient anode materials for SOECs. Herein, a series of novel Y_(0.95-x)Sr_(x)Co_(0.3)Fe_(0.7)O_(3-δ) (YSCF-x) orthorhombic perovskite oxides in the Pnma (62) space group are synthesized as anode materials of SOECs. Physicochemical characterizations and density functional theory calculations reveal that the partial substitution of Y^(3+) by Sr^(2+) increases the oxygen vacancy concentration and mobility as well as improves the electrical conductivity, which contributes to the excellent OER activity of YSCF-x. At 800 °C, the current density of SOEC with YSCF-0.05-Ce0.8Sm0.2O2-δ anode can reach 1.32 A cm^(−2) at 1.6 V, about twice that of SOEC with Y_(0.95-x)Sr_(x)Co_(0.3)Fe_(0.7)O_(3-δ)-Ce_(0.8)Sm_(0.2)O_(2-δ) anode. This work paves a new avenue for the design of advanced anode materials of SOECs.
基金
We gratefully acknowledge financial support from the National Key R&D Program of China(Grant 2017YFA0700102)
the National Natural Science Foundation of China(Grants 92045302,22072146,22002166 and 22002158)
the DNL Cooperation Fund,CAS(DNL201923)
G.X.Wang thanks the financial support from the CAS Youth Innovation Promotion(Grant Y201938).
