Single-crystalline samples of Eu/Ba-filled Sn-based type-Ⅷ clathrate are prepared by the Ga flux method with different stoichiometric ratios. The electrical transport properties of the samples are optimized by Eu dop...Single-crystalline samples of Eu/Ba-filled Sn-based type-Ⅷ clathrate are prepared by the Ga flux method with different stoichiometric ratios. The electrical transport properties of the samples are optimized by Eu doping. Results indicate that Eu atoms tend to replace Ba atoms. With the increase of the Eu initial content, the carrier density increases and the carrier mobility decreases, which leads to an increase of the Seebeck coefficient. By contrast, the electrical conductivity decreases. Finally, the sample with Eu initial content of x = 0.75 behaves with excellent electrical properties, which shows a maximal power factor of 1.51 mW·m^-1K^-2 at 480K, and the highest ZT achieved is 0.87 near the temperature of 483K.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 51262032
文摘Single-crystalline samples of Eu/Ba-filled Sn-based type-Ⅷ clathrate are prepared by the Ga flux method with different stoichiometric ratios. The electrical transport properties of the samples are optimized by Eu doping. Results indicate that Eu atoms tend to replace Ba atoms. With the increase of the Eu initial content, the carrier density increases and the carrier mobility decreases, which leads to an increase of the Seebeck coefficient. By contrast, the electrical conductivity decreases. Finally, the sample with Eu initial content of x = 0.75 behaves with excellent electrical properties, which shows a maximal power factor of 1.51 mW·m^-1K^-2 at 480K, and the highest ZT achieved is 0.87 near the temperature of 483K.