Ta Huy Q, Mendes Rafael G, Liu Yu, Yang Xiaoqin, Luo Jingping, Bachmatiuk Alicja, Gemming Thomas, Zeng Mengqi, Fu Lei, Liu Lijun, Rümmeli Mark H
Soochow Institute for Energy and Materials Innovations, College of Energy, Collaborative Innovation Center of Suzhou, Nano Science and Technology, Key Laboratory of Advanced Carbon Materials, Wearable Energy Technologies of Jiangsu Province, Soochow University, Suzhou, 215006, China.
Institute for Complex Materials, IFW Dresden, P.O. Box D-01171, Dresden, Germany.
Adv Sci (Weinh). 2021 Oct;8(20):e2100619. doi: 10.1002/advs.202100619. Epub 2021 Aug 30.
In recent years, two-dimensional (2D) materials have attracted a lot of research interest as they exhibit several fascinating properties. However, outside of 2D materials derived from van der Waals layered bulk materials only a few other such materials are realized, and it remains difficult to confirm their 2D freestanding structure. Despite that, many metals are predicted to exist as 2D systems. In this review, the authors summarize the recent progress made in the synthesis and characterization of these 2D metals, so called metallenes, and their oxide forms, metallene oxides as free standing 2D structures formed in situ through the use of transmission electron microscopy (TEM) and scanning TEM (STEM) to synthesize these materials. Two primary approaches for forming freestanding monoatomic metallic membranes are identified. In the first, graphene pores as a means to suspend the metallene or metallene oxide and in the second, electron-beam sputtering for the selective etching of metal alloys or thick complex initial materials is employed to obtain freestanding single-atom-thick 2D metal. The data show a growing number of 2D metals/metallenes and 2D metal/ metallene oxides having been confirmed and point to a bright future for further discoveries of these 2D materials.
近年来，二维（2D）材料因其展现出的几种迷人特性而吸引了大量研究兴趣。然而，除了源自范德华层状块状材料的二维材料外，仅实现了少数其他此类材料，并且仍然难以确认它们的二维独立结构。尽管如此，许多金属被预测以二维体系存在。在这篇综述中，作者总结了这些二维金属（即所谓的金属烯）及其氧化物形式（金属烯氧化物）在合成和表征方面的最新进展，这些二维金属和金属烯氧化物是通过使用透射电子显微镜（TEM）和扫描TEM（STEM）原位合成的独立二维结构。确定了形成独立单原子金属膜的两种主要方法。第一种方法是利用石墨烯孔隙来悬浮金属烯或金属烯氧化物，第二种方法是采用电子束溅射对金属合金或厚的复杂初始材料进行选择性蚀刻，以获得独立的单原子厚二维金属。数据表明，已确认的二维金属/金属烯和二维金属/金属烯氧化物的数量不断增加，并预示着这些二维材料的进一步发现前景光明。
