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Cracking of α-LiAlO₂ matrices in molten carbonate fuel cells (MCFC) leads to reduction in the performance. It was demonstrated in this work that the mechanical strength of α-LiAlO2 matrices is improved by heat-treating at 800°C under ambient gas atmosphere. The mechanical strength (2.91MPa) of the heat-treated matrix was enhanced more than 5 fold compared to the non-heat-treated matrix (0.58MPa). The porosity and crystal structure of the α-LiAlO₂ matrices were not changed after the heat-treatment. The wetting behavior and distribution of carbonate in the heat-treated and the non-heat-treated matrix were investigated and compared. Both non-heat-treated and heat-treated α-LiAlO₂ matrices were completelymore » wetted by molten carbonate. The molten carbonate distribution was concentrated right underneath the circular region formed by the molten carbonate drop in the matrix. Non-heat-treated α-LiAlO₂ samples cracked as a result of the complete absorption of molten carbonate, however, the heat-treated α-LiAlO₂ matrices did not crack, presumably due to their enhanced mechanical strength.« less

The standard enthalpy of formation of a compound is the energy associated with the reaction to form the compound from its component elements. The standard enthalpy of formation is a fundamental thermodynamic property that determines its phase stability, which can be coupled with other thermodynamic data to calculate phase diagrams. Calorimetry provides the only direct method by which the standard enthalpy of formation is experimentally measured. However, the measurement is often a time and energy intensive process. We present a dataset of enthalpies of formation measured by high-temperature calorimetry. The phases measured in this dataset include intermetallic compounds with transitionmore » metal and rare-earth elements, metal borides, metal carbides, and metallic silicides. These measurements were collected from over 50 years of calorimetric experiments. The dataset contains 1,276 entries on experimental enthalpy of formation values and structural information. Most of the entries are for binary compounds but ternary and quaternary compounds are being added as they become available. In conclusion, the dataset also contains predictions of enthalpy of formation from first-principles calculations for comparison.« less