Abstract To drive the research and development of two-dimensional (2-D) germanium monosulfide (GeS) applications, a more facile method for obtaining (GeS) single crystals is required. To that end, we first improved the method for synthesizing polycrystalline GeS to reduce the reaction time and prevent the explosion of the quartz ampoule, and this step was carried out inside a horizontal furnace. We also successfully grew a GeS single crystal without a seed crystal by melting this polycrystalline GeS inside a closed, evacuated quartz ampoule using a two-zone horizontal furnace and then employing a vapor transport method. The growth ampoule was specifically designed to prevent the molten GeS from flowing from the evaporation side to the growth side, where the crystal grew through an evaporation–recondensation transition in the temperature range of 654 to 660 ℃. Single-crystal X-ray diffraction was carried out to precisely determine the crystal structure, which revealed that the grown crystal was a GeS single crystal with an orthorhombic structure of the GeS-type (space group Pnma) and lattice parameters of a = 10.5284 (10), b = 3.6584 (3), and c = 4.3166 (4) A. A differential thermal analysis confirmed that the melting point of the grown GeS crystal was 664 ℃.

中文翻译：

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使用两区卧式炉通过从熔融的 GeS 源中蒸汽传输生长一硫化锗 (GeS) 单晶

摘要 为了推动二维 (2-D) 一硫化锗 (GeS) 应用的研究和开发，需要一种更简便的方法来获得 (GeS) 单晶。为此，我们首先改进了合成多晶 GeS 的方法，以减少反应时间并防止石英安瓿爆炸，并且该步骤在卧式炉内进行。我们还通过在封闭的真空石英安瓿中使用两区卧式炉熔化这种多晶 GeS，然后采用蒸汽传输方法，成功地生长出没有晶种的 GeS 单晶。生长安瓿专门设计用于防止熔融的 GeS 从蒸发侧流向生长侧，其中晶体在 654 至 660 ℃ 的温度范围内通过蒸发-再冷凝转变生长。进行单晶X射线衍射以精确确定晶体结构，结果表明生长的晶体为GeS型（空间群Pnma）正交结构的GeS单晶，晶格参数a = 10.5284（ 10), b = 3.6584 (3), and c = 4.3166 (4) A.差热分析证实生长的GeS晶体的熔点为664℃。