Bi_2Te_3纳米粉末的直流电弧等离子体合成

Preparation of Bi_2Te_3 Nanopowder by Direct Current Arc Plasma

以单质Bi,Te粉末为原材料,采用直流电弧等离子体蒸发法制备了Bi2Te3纳米粉末。通过XRD,EDS,TEM和SAED分析方法对Bi2Te3粉末的物相结构、成分和形貌进行了表征。Bi2Te3纳米粉末的平均粒径约为35 nm,粉末呈不规则的多面体结构,还有一些薄片状和棒状的结构,这与Bi2Te3半导体化合物的高度各向异性是一致的。研究了电弧电流和氩气压力对合成Bi2Te3纳米粉末的粒径和产率的影响,随着电弧电流或氩气气压的增加,粉末的粒径和产率都逐渐增大,但产率的增加并不明显。

Starting from elemental bismuth and tellurium,Bi_2Te_3 nanopowder was successfully prepared by direct current arc plasma evaporation technique.Microstructure and morphology of the samples were characterized by X-ray diffractometry（XRD）,transmission electron microscopy（TEM） and selected area electron diffraction（SAED）.Compositional analysis was carried out by X-ray energy dispersive spectroscopy（EDS）.Average particle size of as-synthesized Bi_2Te_3 nanopowder is about 35 nm.Irregular polyhedrons,flake and rod-like structures are consistent with high anisotropy of Bi_2Te_3 semiconductor compound.With increasing arc current or Ar gas pressure,particle size and yield rate of the Bi_2Te_3 nanopowder increase,but the variation of yield rate is not obvious.