Thermoelectric Performance of Ca2Si Synthesized by High-Temperature Melting

Ca2Si was successfully synthesized via a high-temperature melting furnace and a spark plasma sintering process, allowing its thermoelectric properties to be studied. High-temperature melting furnaces were utilized to inhibit the volatilization of Ca elements during the preparation stage, ensuring the production of high-purity Ca2Si. The resistivity of Ca2Si increased gradually with rising temperature and reached 12 mO.cm at 873 K, demonstrating semi-metallic characteristics. In the temperature range of 323 K-873 K, Ca2Si displayed relatively low total thermal conductivity, from 1.1 to 1.7 W.m(-1).K-1. Nevertheless, Ca2Si attained a maximum thermoelectric figure of merit (ZT) of 0.1 due to the atypical behavior and electrical properties of semiconductors. In contrast, Mg2Si achieved a ZT value of 0.32 at 873 K, owing to its exceptional Seebeck coefficient.

Automated summary

Ca2Si was synthesized using a high-temperature melting furnace and spark plasma sintering process for studying its thermoelectric properties. The use of high-temperature melting furnaces prevented Ca element volatilization during preparation, ensuring high-purity Ca2Si production. Ca2Si showed a gradual increase in resistivity with rising temperature, reaching 12 mO.cm at 873K, indicating semi-metallic characteristics. With relatively low thermal conductivity of 1.1 to 1.7 W.m(-1).K-1 in the temperature range of 323K-873K, Ca2Si achieved a maximum thermoelectric figure of merit (ZT) of 0.1 due to its atypical behavior and electrical properties of semiconductors. In contrast, Mg2Si attained a higher ZT value of 0.32 at 873K, primarily because of its exceptional Seebeck coefficient.