溶剂热合成Bi_2Te_3基合金的结构与电学性能

Structures and electric properties of Bi_2Te_3 based alloys prepared by solvothermal synthesis

用溶剂热法合成了二元Bi2Te3和三元Bi1.3Sn0.7Te3合金纳米粉末,并采用热压技术制备了块状热电材料。XRD分析结果表明:Bi Sn Te三元固溶体合金可以直接通过溶剂热合成获得单相产物,而非掺杂Bi2Te3合金需要通过热压等后热处理来实现产物的单一化;热压过程有助于促进反应的完全和晶型的完整,但会导致晶粒的长大。对试样电导率σ和Seebeck系数α的测量结果显示,Bi Sn Te三元固溶体合金比二元Bi Te合金具有更好的电学性能。

Binary Bi_2Te_3 and ternary Bi_(1.3)Sn_(0.7)Te_3 thermoelectric samples were prepared by hot pressing from the solvothermally synthesized nano-powders. The XRD analyses show that a single-phased ternary Bi-Sn-Te alloy can be obtained directly by solvothermal synthesis. Hot pressing can facilitate the integrality of reaction and the crystalline structure, but will induce the grain growth. The measured results of electric conductivity(σ) and Seebeck coefficients(α) of the samples indicate that the ternary Bi-Sn-Te alloy has better electric properties than the binary Bi-Te alloy does.