水热法合成纳米花状二硫化钼及其微观结构表征∗

摘要

本文以钼酸钠、硫代乙酰胺为前驱体,硅钨酸为添加剂,成功用水热法合成高纯度纳米花状二硫化钼。产物特性用X射线衍射(XRD)、能量色散谱(EDS)、扫描电子显微镜(SEM)进行表征。 XRD和EDS图显示实验产物为二硫化钼,且其结晶度和层状堆垛良好。 SEM图谱则表明二硫化钼为纳米花状结构,颗粒直径300 nm左右,由几十上百片花瓣组成,每片花瓣厚度十个纳米左右。通过以硅钨酸为变量的梯度实验,研究发现,硅钨酸对于纳米花状MoS2的形成具有重要作用,不添加硅钨酸,无法形成纳米花状MoS2,此外,硅钨酸的剂量会影响合成MoS2的大小和形貌。本文还对纳米花状二硫化钼的形成机理做了初步的讨论。%High-purity flower-like MoS2 microspheres have been successfully synthesized by hydrothermal method using Na2MoO4 and CH3CSNH2 as precursors, and H4O40SiW12 as an additive. Samples are characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS). XRD and EDS pat-terns show that the as-prepared samples are MoS2, which have good crystallinity with a well-stacked layered structure. SEM images show that the as-prepared MoS2 are composed of flower-like microspheres with a mean diameter about 300 nm, the structures of which are constructed from dozens of hundreds of MoS2 nano-sheet with a thickness of several nanometers. It is also found that the silicotungstic acid plays an important role in the formation of the flower-like MoS2 microspheres, which could affect the size and morphology of the MoS2. Flower-like MoS2 is not found in the as-prepared product without adding silicotungstic acid. A formation mechanism of MoS2 microspheres is tentatively given.