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From planar boron clusters to borophenes and metalloborophenes

Nature Reviews Chemistry volume 1, Article number: 0071 (2017) | Download Citation

Abstract

Elemental boron and its compounds exhibit unusual structures and chemical bonding owing to the electron deficiency of boron. Joint photoelectron spectroscopy and theoretical studies over the past decade have revealed that boron clusters possess planar or quasi-planar (2D) structures up to relatively large sizes, laying the foundations for the discovery of boron-based nanostructures. The observation of the 2D B36 cluster provided the first experimental evidence that extended boron monolayers with hexagonal vacancies were potentially viable and led to the proposition of ‘borophenes’ — boron analogues of 2D carbon structures such as graphene. Metal-doping can expand the range of potential nanostructures based on boron. Recent studies have shown that the CoB18 and RhB18 clusters possess unprecedented 2D structures, in which the dopant metal atom is part of the 2D boron network. These doped 2D clusters suggest the possibilities of creating metal-doped borophenes with potentially tunable electronic, optical and magnetic properties. Here, we discuss the recent experimental and theoretical advances in 2D boron and doped boron clusters, as well as their implications for metalloborophenes.

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Acknowledgements

The experimental work on size-selected boron clusters at Brown University was supported by the US National Science Foundation (Grant No. CHE-1263745). The theoretical work done at Tsinghua University was supported by the National Key Basic Research Special Funds (Grant No. 2013CB834603) and the National Natural Science Foundation of China (Grant Nos 21433005, 91426302 and 21590792) of China. The calculations were performed using supercomputers at the Computer Network Information Center, Chinese Academy of Sciences, Tsinghua National Laboratory for Information Science and Technology, and Guangzhou Tianhe-2 Supercomputing Center.

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  1. Wan-Lu Li, Xin Chen and Jun Li are at the Department of Chemistry, and Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China.

    • Wan-Lu Li
    • , Xin Chen
    •  & Jun Li
  2. Tian Jian, Teng-Teng Chen and Lai-Sheng Wang are at the Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA.

    • Tian Jian
    • , Teng-Teng Chen
    •  & Lai-Sheng Wang

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Correspondence to Jun Li or Lai-Sheng Wang.

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https://doi.org/10.1038/s41570-017-0071