石墨烯硒化钼异质结的制备与光电特性研究

Preparation of graphene/MoSe2 heterojunction and its photoelectric characteristics

研究了石墨烯/硒化钼薄膜异质结的制备及其光电特性。首先,在Si衬底上以硒化钼粉末为原料,采用化学气相沉积法(CVD)沉积硒化钼薄膜;然后,以甲烷为原料在硒化钼薄膜表面利用化学气相沉积法沉积石墨烯膜形成石墨烯/硒化钼异质结。利用原子力显微镜(AFM)观察表明,硒化钼薄膜由许多垂直于表面、直径大约2 nm、高度大约10 nm的纳米线构成,而石墨烯则为许多小片分散在衬底表面。X射线衍射分析表明,硒化钼薄膜在(004)晶面具有很强的取向生长的特性,这与AFM观察到硒化钼薄膜由许多相互平行的纳米线构成相一致。石墨烯/硒化钼异质结对可见光有良好的吸收特性,光照下具有显著的光电流产生,说明石墨烯/硒化钼异质结具有优异的光电特性,在光电器件领域可能有大的应用潜力。

The paper presents the preparation and optoelectronic characteristics of graphene/molybdenum se-lenide(MoSe2) heterojunction. Firstly,MoSe2 powder as raw materials was deposited by a chemical vapor deposition(CVD) method on Si substrates to form MoSe2 film,and then the graphene/MoSe2 heterojunction was formed by growing a graphene layer on the MoSe2 film using methane(CH4) as raw materials. The experimental results of atomic force microscopy(AFM) show that MoSe2 films consist of many nanowires,perpendicular to the surface,about 2 nm in diameter and 10 nm in length,while many small graphene pieces are formed and dispersed on MoSe2 film surface. In addition,the results of X-ray diffraction analysis show that MoSe2 film has a strong orientation growth in the(004) crystal plane,which is consistent with that composed of many parallel nanowires in the AFM picture. Moreover,the graphene/MoSe2 heterojunction is found with good absorption properties in visible light range. A significant photocurrent was generated by illumination on graphene/MoSe2. Therefore,it can be stated that the graphene/MoSe2 heterojunction has good optoelectronic properties and great potential for applica-tion in the field of optoelectronic devices.