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The trigonal system Zintl phase YbZn2Sb2 compound is a promising thermoelectric materials, such as thermoelectric materials research are concentrated in the Yb bit and replace the thermoelectric properties of Zn site elements. This paper developed a quick preparation YbZn2Sb2 based porous thermoelectric materials melt quench spark plasma sintering unbalanced new method, the preparation cycle of YbZn2Sb2 based thermoelectric materials by the traditional process of 22 days down to 17 hours, and this method is successful prepare a nominal composition YbInxZn2 xSb2 (0 LT; ≤ x ≦ 0.8), In-doped YbZn2Sb2-xGex (0 ≤ x ≤ 0.15) and YbIn0.1Zn1.9Sb2-xGex (0 ≤ x ≤ 0.25) Zn site, Sb-bit Ge doped with In and Ge dual doped YbZn2Sb2 based porous thermoelectric materials. All YbZn2Sb2-based thermoelectric materials by main phase YbZn2Sb2 of composition, and a small amount Yb9Zn4.5Sb9 having a layered microstructure, its interior there are a large number of pore size of 20 ~ 100 nm of the nanopore. Unit cell parameters a and c the Zn site In the doping YbInxZn2-xSb2 (x = 0,0.02 0.04,0.05,0.06,0.08,0.1,0.12,0.16,0.2,0.4,0.6,0.8) p-type YbZn2Sb2 based compounds with x increases, IN impurities of approximately 0.1. 300 ~ 875 K, the electric transport properties that: YbInxZn2-xSb2 the electrical conductivity and the thermal conductivity of the porous material within x ≤ 0.08 with the solid solubility limit in the Zn site x increases and reduces, Seebeck coefficient increased with increasing x; x ≥ 0.1 after rising rate of electrical and thermal conductivity, Seebeck coefficient decreased. Porous materials YbInxZn2-xSb2 electric transmission performance are better than the traditional method of preparation of the same ingredients dense bulk material ZT value of a YbZn2Sb2 porous materials 500 K and 875 K, respectively, 0.27 and 0.58, respectively, than the bulk material of the same composition 69% and 12%, respectively. YbIn0.1Zn1.9Sb2 porous material 875 K ZT value the most, reached 0.65, compared with ZT value of (0.53) in the temperature of the bulk material of the same ingredients, increased 23%. Sb bit the Ge doping YbZn2Sb2-xGex (x = 0,0.05,0.08,0.1,0.15) and (In, Ge) doped YbIn0.1Zn1.9Sb2-xGex (x = 0,0.005,0.01,0.03,0.10, 0.15,0.20,0.25) the p type YbZn2Sb2 based porous material within 300 ~ 875 K electric transport properties show with Ge doping x increases, YbZn2Sb2-xGex (x = 0.05) and YbIn0.1Zn1.9Sb2- xGex's electrical and thermal conductivity rate increased, but significantly lower Seebeck coefficient, the material ZT value of a downward trend. Compared with YbZn2Sb2 porous material, YbZn2Sb1.9sGe0.05 conductivity of 300 ~ 875 K is almost equal, but a significant increase in the Seebeck coefficient, 875 K ZT value reached 0.68, a 26% increase, suggesting that trace Ge on YbZn2Sb2 compound Sb doped help improve the performance of its electric transport.
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