The widely studied class of two‐dimensional (2D) materials known as transition metal dichalcogenides (TMDs) are now well‐poised to be employed in real‐world applications ranging from electronic logic and memory devices to gas and biological sensors. Several scalable thin film synthesis techniques have demonstrated nanoscale control of TMD material thickness, morphology, structure, and chemistry and correlated these properties with high‐performing, application‐specific device metrics. In this review, the particularly versatile two‐step conversion (2SC) method of TMD film synthesis is highlighted. The 2SC technique relies on deposition of a solid metal or metal oxide precursor material, followed by a reaction with a chalcogen vapor at an elevated temperature, converting the precursor film to a crystalline TMD. Herein, the variables at each step of the 2SC process including the impact of the precursor film material and deposition technique, the influence of gas composition and temperature during conversion, as well as other factors controlling high‐quality 2D TMD synthesis are considered. The specific advantages of the 2SC approach including deposition on diverse substrates, low‐temperature processing, orientation control, and heterostructure synthesis, among others, are featured. Finally, emergent opportunities that take advantage of the 2SC approach are discussed to include next‐generation electronics, sensing, and optoelectronic devices, as well as catalysis for energy‐related applications.

中文翻译：

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金属和金属氧化物前体薄膜向二维过渡金属二硫属化物和异质结构的两步转化

被广泛研究的一类二维（2D）材料，称为过渡金属二硫属化物（TMD），现在已经准备好用于从电子逻辑和存储设备到气体和生物传感器等实际应用。几种可扩展的薄膜合成技术已经证明了 TMD 材料厚度、形态、结构和化学的纳米级控制，并将这些特性与高性能、特定应用的设备指标相关联。在这篇综述中，重点介绍了 TMD 薄膜合成的特别通用的两步转换 (2SC) 方法。 2SC技术依赖于固体金属或金属氧化物前体材料的沉积，然后在高温下与硫族蒸气发生反应，将前体薄膜转化为晶体TMD。在此，考虑了2SC工艺每个步骤的变量，包括前驱体薄膜材料和沉积技术的影响、转换过程中气体成分和温度的影响，以及控制高质量2D TMD合成的其他因素。 2SC 方法的具体优势包括在不同基材上的沉积、低温处理、取向控制和异质结构合成等。最后，讨论了利用 2SC 方法的新兴机会，包括下一代电子、传感和光电设备，以及能源相关应用的催化。