Resistance of composite materials based on BaCeO3 against the corrosive effects of carbon dioxide and water vapour at intermediate fuel cell operating temperatures

The objective of this work is to analyse the chemical stability of BaCe0.85Y0.15O3-d-Ce0.85Y0.15O2-d (BCY15-YDC15) composite materials at 600 °C and to compare the aforementioned chemical stability with that of pure BCY15. The composite powders were obtained by mixing together powders of BCY15 and YDC15 in the following volume fractions: 90 % BCY15 ? 10 % YDC15, 70% BCY15?30% YDC15, 30% BCY15?70% YDC15, 20% BCY15?80% YDC15 and 10% BCY15 ? 90 % YDC15. After that both powders and sin- tered samples of the BCY15 and the BCY15-YDC15 composites were saturated in two different atmospheres at 600 °C: CO2/H2O (3.1 mol% H2O) and N2/H2O (46.8 mol% H2O). The effects of the previously mentioned atmospheres on the physicochemical properties of the sam- ples were investigated via differential thermal analysis (DTA) combined with thermogravimetric analysis (TG). Furthermore, mass spectrometry was used to analyse the chemical composition of the gases released from the sam- ples during the DTA-TG heating process. The surface and cross-section morphology of the samples were examined by scanning electron microscopy. Moreover, the phase com- position of each sample was studied via X-ray Diffraction. From the combined analysis, it can be concluded that the addition of YDC15 in the composite samples leads to anincrease in resistance against the corrosive effects of CO2. Furthermore, it was determined that all samples maintain stability in the presence of H2O at 600 °C.