Transition metal dichalcogenides (TMDs) show wide ranges of electronic properties ranging from semiconducting, semi-metallic to metallic due to their remarkable structural differences. To obtain 2D TMDs with specific properties, it is extremely important to develop particular strategies to obtain specific phase structures. Phase engineering is a traditional method to achieve transformation from one phase to another controllably. Control of such transformations enables the control of properties and access to a range of properties, otherwise inaccessible. Then extraordinary structural, electronic and optical properties lead to a broad range of potential applications. In this review, we introduce the various electronic properties of 2D TMDs and their polymorphs, and strategies and mechanisms for phase transitions, and phase transition kinetics. Moreover, the potential applications of 2D TMDs in energy storage and conversion, including electro/photocatalysts, batteries/supercapacitors and electronic devices, are also discussed. Finally, opportunities and challenges are highlighted. This review may further promote the development of TMD phase engineering and shed light on other two-dimensional materials of fundamental interest and with potential ranges of applications.

中文翻译：

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TMD纳米材料的最新进展：相变和应用。

过渡金属二硫化碳（TMDs）由于其显着的结构差异而显示出从半导体，半金属到金属的各种电子特性。为了获得具有特定特性的二维TMD，开发特定策略以获得特定相结构非常重要。阶段工程是一种可控地实现从一个阶段到另一个阶段的转换的传统方法。通过控制此类转换，可以控制属性并访问一系列属性，否则将无法访问。然后，非凡的结构，电子和光学特性导致了广泛的潜在应用。在这篇综述中，我们介绍了2D TMD及其多晶型物的各种电子性质，以及相变和相变动力学的策略和机理。此外，还讨论了二维TMD在能量存储和转换中的潜在应用，包括电子/光催化剂，电池/超级电容器和电子设备。最后，强调了机遇与挑战。这项审查可能会进一步促进TMD相工程的发展，并为其他具有基本用途和潜在应用范围的二维材料提供启发。