Polycrystalline samples of Bi 1.5 Pb 0.5 Sr 2-x La x Co 2 O y （x = 0.1, 0.2, 0.3） with a layered structure were prepared by solid-state reaction method. All samples are p-type semiconductors. The thermoelectric prop...Polycrystalline samples of Bi 1.5 Pb 0.5 Sr 2-x La x Co 2 O y （x = 0.1, 0.2, 0.3） with a layered structure were prepared by solid-state reaction method. All samples are p-type semiconductors. The thermoelectric properties, namely, the electric resistivity （ρ）, Seebeck coefficient （S）, and power factor （S 2 /ρ） of the samples are dependent on chemical composition. The values of ρ, S, and S 2 /ρ increase with an increase in temperature for all samples. The substitution of Pb 2＋ for Bi 3＋ and La 3＋ for Sr 2＋ improves the thermoelectric properties of the Bi 2 Sr 2 Co 2 O y system owing to the simultaneous decrease of electric resistivity and increase of Seebeck coefficient. As a result, the optimal thermoelectric property has been obtained in Bi 1.5 Pb 0.5 Sr 1.7 La 0.3 Co 2 O y and the power factor can reach 2.1 × 10-4 W·m-1 K-2 at 998 K.展开更多
基金supported by the Program for Innovative Research Team (in Science and Technology) (No. 2009IRTHNIE05) in Henan Institute of Engineeringthe Foundation for University Key Teachers of Henan Province (No. 2008136)+1 种基金the Natural Science Fund of Henan Education Department, China (No. 2010C140001)the Youth Fund of Henan Institute of Engineering (No. Y10021)
文摘Polycrystalline samples of Bi 1.5 Pb 0.5 Sr 2-x La x Co 2 O y （x = 0.1, 0.2, 0.3） with a layered structure were prepared by solid-state reaction method. All samples are p-type semiconductors. The thermoelectric properties, namely, the electric resistivity （ρ）, Seebeck coefficient （S）, and power factor （S 2 /ρ） of the samples are dependent on chemical composition. The values of ρ, S, and S 2 /ρ increase with an increase in temperature for all samples. The substitution of Pb 2＋ for Bi 3＋ and La 3＋ for Sr 2＋ improves the thermoelectric properties of the Bi 2 Sr 2 Co 2 O y system owing to the simultaneous decrease of electric resistivity and increase of Seebeck coefficient. As a result, the optimal thermoelectric property has been obtained in Bi 1.5 Pb 0.5 Sr 1.7 La 0.3 Co 2 O y and the power factor can reach 2.1 × 10-4 W·m-1 K-2 at 998 K.
