Thermoelectric properties of URu2Si2 and U2Ru3Si5

The new possibility of uranium noble metal silicides for thermoelectric materials was investigated by the analogy with transition-metal silicides having good thermoelectric power. The Seebeck coefficient and electrical resistivity of URu2Si2 and U2Ru3Si5 were measured in the temperature range from 300 to 1100 K and Hall coefficient at room temperature. The Seebeck coefficients of URu2Si2 and U2Ru3Si5 were obtained to be −48.9 and −32.8 μV K−1 at 1100 K, respectively. The temperature dependences of the electrical resistivities for URu2Si2 and U2Ru3Si5 were small, which are similar to that of uranium metal rather than that of silicon semiconductor. As thermoelectric materials for high temperatures, URu2Si2 and U2Ru3Si5 were thought to be not promising.