Conductivity of perovskites La$_{0.9}$Sr$_{0.1}$Sc$_{1-x}$Fe$_{x}$O$_{3-\alpha}$ ($x$ = 0.003–0.47) in oxidizing and reducing atmospheres

The conductivity of single-phase ceramic materials based on proton-conducting perovskite La$_{0.9}$Sr$_{0.1}$Sc$_{1-x}$Fe$_{x}$O$_{3-\alpha}$ containing from 0.3 to 47 at % Fe in the scandium sublattice has been studied. Synthesis has been performed by burning with ethylene glycol. Measurements have been carried out by the four-probe (500–900$^\circ$C) and impedance (100–500$^\circ$C) methods in oxidizing and reducing atmospheres, as well as at different pressures $p_{\mathrm{О}_2}$ (2.1 $\cdot$ 10$^{4}$–10$^{-15}$ Pa) and $p_{\mathrm{H}_2\mathrm{O}}$ (0.04–2.5 kPa). Substitution of scandium with iron significantly decreases the proton conductivity.