Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Löbdergraben 32, D-07743 Jena, Germany.
School of Materials Science and Engineering, Harbin Institute of Technology, West Da-Zhi Street 92, 150001 Harbin, China.
Sci Rep. 2017 Mar 8;7:43611. doi: 10.1038/srep43611.
Layered (BiIn)Te-InTe (x = 0.075) composites of pronounced anisotropy in structure and thermoelectric properties were produced by zone melting and subsequent coherent precipitation of InTe from a (BiIn)Te (x > 0.075) matrix. Employing solid state phase transformation, the BiTe/InTe interface density was tuned by modifying the driving force for InTe precipitation. The structure-property relationship in this strongly anisotropic material is characterized thoroughly and systematically for the first time. Unexpectedly, with increasing BiTe/InTe interface density, an increase in electrical conductivity and a decrease in the absolute Seebeck coefficient were found. This is likely to be due to electron accumulation layers at the BiTe/InTe interfaces and the interplay of bipolar transport in BiTe. Significantly improved thermoelectric properties of BiTe-InTe composites as compared to the single phase (BiIn)Te solid solution are obtained.
通过区域熔炼和随后从（BiIn）Te（x>0.075）基体中均匀沉淀 InTe，制备出结构和热电性能具有明显各向异性的层状（BiIn）Te-InTe（x=0.075）复合材料。通过固态相变，通过改变 InTe 沉淀的驱动力来调整 BiTe/InTe 界面密度。首次对这种强各向异性材料的结构-性能关系进行了全面而系统的研究。出乎意料的是，随着 BiTe/InTe 界面密度的增加，发现电导率增加而绝对塞贝克系数减小。这可能是由于 BiTe/InTe 界面处的电子积累层和 BiTe 中的双极输运相互作用所致。与单相（BiIn）Te 固溶体相比，BiTe-InTe 复合材料的热电性能得到显著改善。
