SnSe/Bi2Se3纳米片异质结的制备

Preparation of SnSe/BiSe Nanosheet Heterojunctions

半导体和拓扑绝缘体是两类重要的功能材料,其纳米异质结可能具有特殊的物性和应用.本文利用两步法制备了半导体SnSe和拓扑绝缘体Bi2Se3纳米片异质结,对样品的结构和形貌进行了表征.首先用溶剂热技术制备出形貌均匀的Bi2Se3纳米片,再以之为衬底,以Sn Se粉末为蒸发源,利用真空热蒸发技术制备SnSe/Bi2Se3纳米片异质结.X射线衍射和扫描电子显微术表征了样品的物相和形貌,结果显示在三方结构的Bi2Se3纳米片上沉积得到了均匀分布的正交相Sn Se纳米颗粒,可以通过热蒸发实验参数调控纳米颗粒的厚度和密度.本研究的实验方法简便易行,得到的新型纳米异质结在近红外光电探测方面有潜在应用.

Semiconductors and topological insulators are two kinds of important functional materials,and their nanoscale heterojunctions may have unique physical properties and applications.In this paper,heterojunctions of semiconductor Sn Se and topological insulator Bi2Se3 nanosheets were prepared by a two-step method,and the structure and morphology of the samples were characterized.First,Bi2Se3 nanosheets with uniform morphology were prepared by a solvothermal technique,and then Sn Se nanoparticles were deposited on the as-prepared Bi2Se3 nanosheets by vacuum thermal evaporation technique to form heterojunctions using Sn Se powder as the evaporation source.The X-ray diffraction(XRD)and scanning electron microscopy(SEM)were employed to characterize the phase and morphology of the samples.The results showed that the uniformly distributed orthorhombic Sn Se nanoparticles were deposited on the trigonal Bi2Se3 nanosheets,and the thickness and density of the nanoparticles were controlled by thermal evaporation parameters.The method of this study is facile,and the novel nanoscale heterojunctions have potential applications in the field of infrared photoelectric detection.