微波合成Mg2Si1-xSnx热电固溶体

为了解决传统方法制备Mg2Si1-xSnx(0≤x≤1.0)固溶体过程中带来Mg的氧化和挥发等问题,引进微波低温合成法制备Mg2Si1-xSnx热电固溶体,用XRD及SEM分析手段对合成的块体的物相和形貌进行表征,并研究Mg2Si1-xSnx化合物的热电特性和在微波场中的加热特性以及合成工艺对Mg2Sil xSnx压坯制备的影响。结果表明:Mg2Si1-xSnx压坯在微波场中的加热升温曲线与Mg2Si1-xSnx压坯密度相关,随压坯密度增大,升温速率降低;XRD分析表明在微波辐射下Mg2Si1-xSnx形成了良好的固溶体;在测试温度范围内,Mg2Si1-xSnx在500 K温度下最高的ZT值达到0.26。

Synthesis of Mg2Si1-xSnx thermoelectric solid solutions by microwave irradiation

In order to reduce the oxidizing and volatilizing caused by Mg element in the traditional methods for synthesizing Mg2Si1-xSnx(0≤x≤1.0) solid solutions,microwave irradiation techniques have been used in preparing them as thermoelectric materials and thermoelectric properties of Mg2Si1-xSnx were studied.The heating behavior of Mg,Si and Sn fixed powder was investigated under microwave irradiation.X-ray diffraction(XRD) and SEM were also used to characterize the powders.The results suggest that the temperature-rising rate is dependent on the initial density of the compact and higher compact density provides lower heating rate while power setting are fixed.X-ray diffraction(XRD) patterns show that Mg2Si1-xSnx-solid solutions have been well formed under microwave irradiation.The maximum dimensionless merit figure,ZT,of about 0.26 was obtained for Mg2Si1-xSnx at 500 K.