Microwave direct synthesis and thermoelectric properties of Mg_(2)Si by solid-state reaction  

Mg_(2)Si的微波固相合成及其热电性能(英文)

作　　者：周书才[1,2] 白晨光[2] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400044 [2]重庆科技学院冶金与材料工程学院,重庆401331

出　　处：《Transactions of Nonferrous Metals Society of China》2011年第8期1785-1789,共5页中国有色金属学报（英文版）

基　　金：Project (2009BB4228) supported by the Natural Science Foundation Project of Chongqing Science and Technology Commission,China;Project (CK2010Z09) supported by the Research Foundation of Chongqing University of Science and Technology,China

摘　　要：In order to reduce the oxidation and volatilization caused by Mg element in the traditional methods for synthesizing Mg2Si compounds,Mg2Si thermoelectric materials were prepared by solid state reaction and microwave radiation techniques.Structure and phase composition of the materials were investigated by X-ray diffraction.The electrical conductivity,Seebeck coefficient and thermal conductivity were measured as a function of temperature from 300 to 700 K.It is found that high purity Mg2Si powders can be obtained with excessive content of 8% Mg from the stoichiometric Mg2Si at 853 K and 2.5 kW for 30 min.A maximum dimensionless figure of merit,ZT,of about 0.13 was obtained for Mg2Si at 600 K.为了解决Mg2Si传统制备方法中Mg的氧化、挥发等问题,采用微波低温固相反应法合成Mg2Si热电材料。用XRD分析手段研究合成产物的结构及相组成。在300到700K的温度范围内,对材料的电导率、Seebeck系数和热导率随温度的变化进行测量。结果表明,当Mg过量8%、加热功率为2.5kW时,于853K保温30min,可以得到单相Mg2Si热电化合物。在测试温度范围内,Mg2Si具有较高的品质因数ZT值,在600K温度下达到0.13。

关 键 词：MG2SI thermoelectric materials solid state reaction microwave synthesis 

分 类 号：O614.22[理学—无机化学]