In the past decades, group IV nanowires and nanoparticles have been the subject of extensive research. Beside tremendous progress in morphological control and integration in advanced device architectures, research on allotropes and metastable compositions has gained considerable interest. Several new approaches now allow the controlled formation of specific allotropes in the nanostructured form as well as chemical compositions not attainable by traditional synthesis protocols. The conditions applied to form these metastable solid solutions and allotropes are usually far from thermodynamic equilibrium or rely on unconventional templates. The increased interest in the field of metastable group IV nanostructures arises from their altered physical properties, including tunable, direct bandgaps with energies equivalent to the near- to mid-infrared spectral region as described for materials such as Ge_1–xSn_x and hexagonal Si_1–xGe_x. The implementation of these material characteristics in complementary metal oxide semiconductor (CMOS) processes are desirable for applications in electronics, optoelectronics, sensors, optics, etc. but also their use as nonsurface bound nanoparticles in sensing, nanobiotechnology and nanomedicine can offer additional opportunities. This review article highlights both the important advancements and still open questions for the continued development of these nanoscaled materials for next-generation device concepts.

中文翻译：

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亚稳IV组同素异形体和固溶体：纳米颗粒和纳米线

在过去的几十年中，IV族纳米线和纳米颗粒已经成为广泛研究的主题。除了在高级器件架构中的形态控制和集成方面取得了巨大进展之外，同素异形体和亚稳成分的研究也引起了极大的兴趣。现在有几种新方法可以控制形成纳米结构形式的特定同素异形体，以及传统合成方法无法达到的化学组成。用于形成这些亚稳态固溶体和同素异形体的条件通常远离热力学平衡或依赖于非常规模板。人们对亚稳IV类纳米结构的兴趣日益浓厚，原因是它们的物理性质发生了变化，包括可调，_{1- x} Sn _x和六角形Si _{1- x} Ge _x。互补金属氧化物半导体（CMOS）工艺中这些材料特性的实现对于电子，光电，传感器，光学等方面的应用是理想的，但是它们在传感，纳米生物技术和纳米医学中作为非表面结合的纳米颗粒的使用也可以提供更多的机会。这篇综述文章重点介绍了这些纳米级材料在下一代设备概念上的持续开发所取得的重要进展和尚待解决的问题。