Abstract Two dimensional MoSe2 mono and few layer were prepared by the atmospheric pressure chemical vapor deposition (CVD). It is essential to understand completely the growth and nucleation mechanism to improve the crystalline quality and size of two dimensional transition metal dichalcogenides materials using CVD. Three different types of MoSe2 surface structure were identified for the different growth temperatures. By changing the growth temperatures, the concentration of MoO3-x and Se vapor precursors vary which derive different nucleation mechanism. Low vapor concentration of reactants leads to mono and bi layer MoSe2 due to 2D planar nucleation while higher concentration of reactants facilitates the self-seeding role that leads to few and multilayers MoSe2. The presence of the defects in monolayer was confirmed by photoluminescence spectra analysis. The surface friction of the mono and few layers were studied experimentally using the lateral force microscopy. The surface friction of MoSe2 depends on the number of layers presents in the surface flakes.

中文翻译：

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CVD 生长的 2D 二硒化钼：形态学、光谱学和机械表征

摘要 采用常压化学气相沉积(CVD)法制备二维MoSe2单层和少层。必须完全了解生长和成核机制，以改善使用 CVD 的二维过渡金属二硫属元素化物材料的晶体质量和尺寸。针对不同的生长温度确定了三种不同类型的 MoSe2 表面结构。通过改变生长温度，MoO3-x 和 Se 蒸气前驱体的浓度会发生变化，从而产生不同的成核机制。由于 2D 平面成核，反应物的低蒸气浓度导致单层和双层 MoSe2，而较高浓度的反应物促进自接种作用，导致少量和多层 MoSe2。通过光致发光光谱分析证实了单层中缺陷的存在。使用侧向力显微镜通过实验研究单层和少数层的表面摩擦。MoSe2 的表面摩擦取决于表面薄片中的层数。