An efficient and prospective self-assembled hybrid electrocatalyst for symmetrical and reversible solid oxide cells

In view of the high catalytic activity, enhanced oxygen-ion transport and good stability, the self-assembled hybrid electrocatalyst can be used for symmetrical and reversible solid oxide cells (RSOCs). Herein, a new Ni-free ceramic fuel electrode can be obtained by in situ annealing the orthorhombic perovskite Pr0.6Sr0.4FeO3-delta (PSF) in H-2 at 850 degrees C for 2 h, consisting of orthorhombic perovskite matrix with nano Ruddlesden-Popper oxide (RP/O-PSF). Symmetrical RSOCs consisting of RP/O-PSF fuel electrode, La0.9Sr0.1Ga0.8Mg0.2O3-delta (LSGM) electrolyte and PSF air electrode (PSFILSGMIPSF) were fabricated and the electrochemical performance was evaluated. The maximum power density of the cell under solid oxide fuel cell (SOFC) mode is 591 mW/cm(2) at 800 degrees C, and the current density of the cell under solid oxide electrolysis cell (SOEC) mode is -1388 mA/cm(2) at 800 degrees C with an applied electrolysis voltage of 1.6 V. The polarization resistances of cell under SOFC mode and SOEC mode are 0.152 Omega cm(2) (OCV-0.2 V) and 0.126 Omega cm(2) (OCV + 0.2 V), respectively, demonstrating an excellent catalytic activity of RP/O-PSF towards the water electrolysis process compared with hydrogen oxidation reaction (HOR) owing to the accelerated transfer rate of oxygen ions. In addition, the desirable long-term stability indicates the fact that RP/O-PSF hybrid electrode is such a suitable and prospective candidate for symmetrical and reversible solid oxide cells. (C) 2020 Elsevier Ltd. All rights reserved.