In this work, we report the synthesis and characterization of mixed phase Nb_1+xS₂ nanoflakes prepared by chemical vapor deposition. The as-grown samples show a high density of flakes (thickness ∼50 nm) that form a continuous film. Raman and X-ray diffraction data show that the samples consist of both 2H and 3R phases, with the 2H phase containing a high concentration of Nb interstitials. These Nb interstitials sit in between the NbS₂ layers to form Nb_1+xS₂. Cross-sectional Energy Dispersive Spectroscopy analysis with transmission electron microscopy suggests that the 2H Nb_1+xS₂ region is found in thinner flakes, while 3R NbS₂ is observed in thicker regions of the films. The evolution of the phase from 2H Nb_1+xS₂ to 3R NbS₂ may be attributed to the change of the growth environment from Nb-rich at the start of the growth to sulfur-rich at the latter stage. It was also found that the incorporation of Nb interstitials is highly dependent on the temperature of the NbCl₅ precursor and the position of the substrate in the furnace. Samples grown at high NbCl₅ temperature and with substrate located closer to the NbCl₅ source show higher incorporation of Nb interstitials. Electrical measurements show linear I–V characteristics, indicating the metallic nature of the Nb_1+xS₂ film with relatively low resistivity of 4.1 × 10⁻³ Ω cm.

中文翻译：

---

化学气相沉积法合成3R和2H Nb1 + xS2混合金属纳米片

在这项工作中，我们报告了化学气相沉积制备的混合相Nb _{1+ x} S ₂纳米薄片的合成和表征。所生长的样品显示出高密度的薄片（厚度约50 nm），形成了连续的薄膜。拉曼和X射线衍射数据表明，样品由2H和3R相组成，而2H相包含高浓度的Nb间隙。这些Nb间隙位于NbS ₂层之间，形成Nb _{1+ x} S ₂。透射电子显微镜的截面能量色散光谱分析表明，2H Nb _{1+ x} S ₂在较薄的薄片中发现了该区域，而在较厚的薄膜中发现了3R NbS ₂。从2H Nb _{1+ x} S ₂到3R NbS ₂的相演变可能归因于生长环境从生长开始时的富Nb到后期的富硫环境的变化。还发现Nb间隙的掺入高度依赖于NbCl ₅前体的温度和炉中衬底的位置。在较高的NbCl ₅温度下生长且样品位于靠近NbCl ₅源的样品显示出较高的Nb间隙掺入率。电气测量显示线性I– V特性，表明Nb _{1+ x} S ₂膜的金属性质具有较低的电阻率，为4.1×10 ^-3Ωcm。