Mg2Si0.5Sn0．5Sbx固溶体的快速制备及其热电性能优化  

Fast Preparation and Optimized Thermoelectric Properties of Mg2 Si0. 5 Sn0.5 Sbx Solid Solutions

作　　者：郑亮[2] 张忻[1] 刘洪亮[1] 韩志明[1] 李松浩[1] 周子群[1] 路清梅[1] 张久兴[1,2] 刘燕琴[1] ZHENG Liang ZHANG Xin LIU Hong-liang HAN Zhi-ming LI Song-hao ZHOU Zi-qun LU Qing-mei ZHANG Jiu-xing LIU Yan-qin(College of Materials Science and Engineering, Beijing University of Technology, The key Laboratory of Advanced Functional Materials, Ministry of Education, Beijing 100124, China School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China)

机构地区：[1]北京工业大学材料科学与工程学院新型功能材料教育部重点实验室,北京100124 [2]合肥工业大学材料科学与工程学院,合肥230009

出　　处：《功能材料与器件学报》2016年第4期56-62,共7页Journal of Functional Materials and Devices

基　　金：国家自然科学基金项目（50801002）,北京市教育委员会科技计划面上项目（KM201510005001）

摘　　要：采用感应熔炼结合放电等离子烧结技术成功制备了单相Mg2Si0.5Sn0.5Sbx（0≤x≤0．015）系列固溶体。从XRD和XRF分析结果可以看出，该制备方法能够很好地避免Mg元素的氧化和有效控制Mg的含量，且Sb元素成功进入了固溶体的晶格位置。热电性能测试结果表明，所有样品的Seebeck系数均为负值，且随着Sb掺杂量x的增加，电阻率大幅度降低，呈现出n型半导体输运特性；Sb元素进入固溶体晶格位置产生晶格畸变，从而增加了声子散射，降低了晶格热导率，所以掺杂Sb样品的晶格热导率明显低于未掺杂样品。Sb掺杂样品的无量纲热电优值ZT明显高于未掺杂样品，其中Sb掺杂量x=0．01成分样品Mg2Si0.5Sn0.5Sb0.1具有最大ZT值，并在700K附近取得最大值约为0．56。The single-phase Mg2 Si0.5 Sn0.5 Sbx （0 ≤ x ≤0. 015 ） solid solutions were prepared by an induction melting and Spark Plasma Sintering method. The analyzing results of the XRD and XRF shows that this method can effectively avoid the magnesium oxide and control the magnesium content. What＇ s more, the Sb can successfully enter the solid solutions lattice sites. The measurement results of the thermoelectric properties indicate that all the samples of the Seebeck coefficient a are negative and the electrical resistivity .9 decreases obviously with the increasing Sb -doped, and showing that the solid solutions are n -type conductivity. The Sb- doped solid solutions caused lattice distortion and increased phonon scattering, thereby reducing the lattice thermal conductivity. Therefore, the lattice thermal conductivity of Sb - doped samples is lower than the undoped sample. The dimensionless figure of merit ZT of Sb - doped samples is obviously higher than the undoped sample, and the ZT for Mg2Si0.5 Sn0.5 Sb0. 1 sample reaches its highest value of 0.56 at 700K.

关 键 词：Mg2Si基热电材料 Sb掺杂 热电性能 放电等离子烧结 晶格热导率 

分 类 号：TB34[一般工业技术—材料科学与工程]