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在Zn?Sb二元相图固相线以下使Zn和Sb粉末反应并随炉冷却,合成一系列Zn1+xSb(x=0,0.05,0.1,0.15,0.25,0.3)材料,分析Zn–Sb相图中心区域的相形成和热电性能.在此过程中,非化学计量比的混合粉末结晶形成ZnSb和 β-Zn4Sb3相的组合.然后,将材料研磨并热压成致密的ZnSb/β-Zn4Sb3复合材料.X射线衍射、高分辨率透射电镜和电子能量损失谱分析均未发现Sb、Zn元素或其他相.所有材料的热电性能都可以归结为ZnSb和β-Zn4Sb3相的热电行为的结合,并由每种材料中的主相所决定,Zn1.3Sb复合材料具有最好的热电性能.研究发现,Ge掺杂可大幅增加Zn1.3Sb的Seebeck系数且显著提高其功率因数,540 K时达1.51 mW·m?1·K?2.总之,Zn1.28Ge0.02Sb具有优异、稳定的ZT值,650 K时为1.17.“,”The phase formation and thermoelectric (TE) properties in the central region of the Zn?Sb phase diagram were analyzed through synthesizing a series of Zn1+xSb (x=0, 0.05, 0.1, 0.15, 0.25, 0.3) materials by reacting Zn and Sb powders below the solidus line of the Zn?Sb binary phase diagram followed by furnace cooling. In this process, the nonstoichiometric powder blend crystallized in a combination of ZnSb and β-Zn4Sb3 phases. Then, the materials were ground and hot pressed to form dense ZnSb/β-Zn4Sb3 composites. No traces of Sb and Zn elements or other phases were revealed by X-ray diffraction, high resolution transmission electron microscopy and electron energy loss spectroscopy analyses. The thermoelectric properties of all materials could be rationalized as a combination of the thermoelectric behavior of ZnSb and β-Zn4Sb3 phases, which were dominated by the main phase in each sample. Zn1.3Sb composite exhibited the best thermoelectric performance. It was also found that Ge doping substantially increased the Seebeck coefficient of Zn1.3Sb and led to significantly higher power factor, up to 1.51 mW·m?1·K?2 at 540 K. Overall, an exceptional and stable TE figure of merit (ZT) of 1.17 at 650 K was obtained for Zn1.28Ge0.02Sb.