Oxide cathodes for electrochemical devices made with the use of a nanostructured composition material

The possibility of using the LnO x mischmetal (Ln = Ce, La, Nd, Pr, Sm) for preparation of cathodes for solid-oxide fuel cells with the supported YSZ electrolyte is studied. The electrical and electrochemical characteristics of Ln-Mn-O electrodes with the ratio of all lanthanides contained in the mischmetal except for cerium to manganese Ln: Mn = 1: 1 and also of a material comprised of Ln-Mn-O and La0.8Sr0.2MnO3 are studied. The latter electrode material that contains 35–40 wt % of Ln-Mn-O and was sintered at 1200°C has the specific ohmic resistance of 0.1 Ω cm at 800°C. The polarization conductivity is compared for electrodes made of 100% Ln-Mn-O, 40 wt % Ln-Mn-O + 60 wt % La0.8Sr0.2MnO3, and 100% La0.8Sr0.2MnO3 in the initial state and after their modification through the introduction of an electrocatalyst (PrO2 − x ). The highest polarization conductivity is typical of Ln-Mn-O + (La, Sr)MnO3 electrodes containing 40 wt % Ln-Mn-O and PrO2 − x . The polarization conductivity of these electrodes is found to be 25 S/cm2 at 800°C.