Structural and Electrical Properties of Gadolinia-doped Ceria Mixed with Alkali Earth Carbonates for SOFC Applications

摘要

The properties of composite materials based on mixtures of gadolinium-doped ceria (GDC) and Li_2CO_3-K_2CO_3 are analyzed as potential SOFC electrolytes. In a temperature range higher than 500℃, their ionic conductivity is significantly higher than for single GDC. Discontinuities were found in the conductivity Arrhenius diagram (σ vs. 1/T) around the melting point of the carbonate mixture (490℃), showing, at least partially, the contribution of molten carbonates. At this stage, precise mechanisms are still under analysis.