Electrochemical Properties of Composite Cathode Materials Pr1.95La0.05CuO4–Ce0.9Gd0.1O1.95 for Intermediate Temperature Solid Oxide Fuel Cells

Resumo

The electrochemical properties are studied for composite electrodes Pr_1.95La_0.05CuO₄(PLCO)–xCe_0.9Gd_0.1O_1.95(GDC), where x = 20, 30, 40, and 50 wt % GDC with the aim of finding the composition with the best electrochemical efficiency in the oxygen reduction reaction. Varying the temperature of sintering of the PLCO–xGDC electrode layer to the surface of GDC solid electrolyte shows that the minimum polarization resistance (R_η) is reached at the temperature of 850°C. For the PLCO–xGDC composition containing 40 wt % GDC, in the temperature range of 600–750°C, the maximum electrochemical activity in oxygen reduction reaction is observed as indicated by 10-fold decrease in R_η as compared with single-phase PLCO (from 0.87 (x = 0) to 0.08 Ω cm² (x = 40) at 700°C in air). According to the data obtained, the PLCO–40GDC composite can be considered as a promising cathode material for intermediate temperature solid oxide fuel cells.