Abstract The two-dimensional (2D) inorganic material Nb3I8, which can be separated into atomic planes, was synthesized through a vapor transport reaction between niobium and iodine. High-purity and cm scale large Nb3I8 crystals were obtained by controlling the growth temperature (600–700 °C) and the stoichiometric ratio between niobium and iodine (using excess I2 condition, niobium: iodine = 3:9). The semiconductor characteristics were measured by the change of electrical conductivity with temperature (increased conductivity with temperature in the range of 100 K–300 K), and have a band gap of ∼1 eV (∼1200 nm) through Infrared (IR)-visible light absorption analysis. Based on these characteristics, the device characteristics of detecting IR near 1200 nm region were verified. Besides few-layers of Nb3I8 was acquired by the mechanical exfoliation method, and experimentally observed by atomic force microscopy (AFM). This 2D material is expected to have an important role in developing another 2D materials and in new nano-optoelectronic devices using it.

中文翻译：

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范德华二维材料Nb3I8的大面积合成及其红外探测应用

摘要 通过铌和碘之间的蒸气传输反应合成了可分离成原子平面的二维 (2D) 无机材料 Nb3I8。通过控制生长温度（600-700°C）和铌碘之间的化学计量比（使用过量 I2 条件，铌：碘 = 3:9），可以获得高纯度和 cm 级大 Nb3I8 晶体。半导体特性是通过电导率随温度的变化来测量的（电导率随温度在 100 K-300 K 范围内增加），并且通过红外（IR）-可见光具有约 1 eV（约 1200 nm）的带隙光吸收分析。基于这些特性，验证了检测 1200 nm 附近 IR 区域的器件特性。此外，通过机械剥离方法获得了几层 Nb3I8，并通过原子力显微镜 (AFM) 进行了实验观察。这种二维材料有望在开发另一种二维材料和使用它的新型纳米光电器件中发挥重要作用。