High-Performance Sr_0.95Fe_0.8Mo_0.1Ni_0.1O_3−δ Electrode for Reversible Symmetrical Solid Oxide Cells

Abstract

Reversible symmetrical solid oxide cells (RS-SOCs) have attracted much attention due to their high energy conversion efficiency and fabrication simplicity. In this study, 10% Fe was substituted with Ni in the B-site of Sr0.9Fe0.9Mo0.1O3−δ to enhance the electrochemical performance of H2O electrolysis. The characterization results and theoretical calculations indicated that Ni doping decreased the adsorption and reaction energy barrier of intermediates of H2O electrolysis on the Sr0.95Fe0.8Mo0.1Ni0.1O3−δ’s (111) surface, which promoted the kinetics of the electrode reaction, thus fabricating electrochemical activity and resulting in higher reaction dynamics. Consequently, a high power density of 1.145 W cm−2 at 850 °C on a symmetrical cell was achieved in the solid oxide fuel cell (SOFC) mode, and a current density of 3.995 A cm−2 was obtained at 850 °C and 1.6 V in the solid oxide electrolysis cell (SOEC) mode, indicating the Sr0.9Fe0.8Mo0.1Ni0.1O3−δ oxide to be a promising SOFC electrode for power production and SOEC electrode for H2 production.

Keywords

• symmetrical solid oxide electrochemical cell
• perovskite oxides
• strontium ferrite
• steam splitting
• Ni doping