Electrochemical Performances of New Pr‐Doped Robust Cobalt‐Free Perovskite Sr₂Fe_1.5Mo_0.5O_6-δ as Electrode for Symmetrical Solid Oxide Fuel Cells

Abstract

Solid oxide electrochemical devices, such as fuel cells and electrolyzers, are the subject of research due to their wide range of applications. Electrochemical devices with symmetric, that is, chemically identical electrodes, have been actively investigated in recent years. This design of cells can significantly reduce the time and cost of fabrication and improve start‐up time by eliminating the fuel electrode reduction step. A serious challenge in the development of symmetrical cells is to find electrode materials that are equally effective in both air and fuel (hydrogen, methane, carbon monoxide, etc.) atmospheres. One such material is Sr2Fe1.5Mo0.5O6-δ (SFM). SFM exhibits satisfactory electrical conductivity and electrochemical activity, high stability in oxidizing and reducing atmospheres, and under redox cycling of a gas environment. This paper presents, for the first time, the results of SFM studies in which a fraction of the strontium cations is replaced by praseodymium. The praseodymium cation is mainly interesting because it has two oxidation states, +3 and +4, which can positively influence the transport properties of SFM, such as electrical conductivity and electrochemical activity in various gas mixtures.