Boosting electrocatalytic performance of Ruddlesden-Popper type Fe-based cathode catalysts by La and Ni co-doping for solid oxide fuel cells

Exploring advanced electrode materials with high electrochemical performance and sufficient durability is crucial to the commercialization of solid oxide fuel cells (SOFCs). Herein, a Ruddlesden-Popper Sr2·9La0·1Fe1·9Ni0·1O7−δ (SLFN) oxide is systematically evaluated as efficient oxygen electrode material. La and Ni co-doping strategy demonstrates improved oxygen desorption ability and promoted electrochemical activity of pristine Sr3Fe2O7−δ (SF) toward oxygen reduction react (ORR). Further, the ORR process of the SLFN electrode is probed by electrochemical impedance spectroscopy (EIS) and distribution of relaxation time (DRT) technique. The button cell with the SLFN cathode delivers a peak power density of 1.01 W cm−2 at 700 °C, along with desirable stability over a period of 60 h. This study offers a feasible strategy for developing Ruddlesden-Popper type cathode candidates for SOFCs.