The synthesis of 2D materials with no analogous bulk layered allotropes promises a substantial breadth of physical and chemical properties through the diverse structural options afforded by substrate-dependent epitaxy. However, despite the joint theoretical and experimental efforts to guide materials discovery, successful demonstrations of synthetic 2D materials have been rare. The recent synthesis of 2D boron polymorphs (that is, borophene) provides a notable example of such success. In this Perspective, we discuss recent progress and future opportunities for borophene research. Borophene combines unique mechanical properties with anisotropic metallicity, which complements the canon of conventional 2D materials. The multi-centre characteristics of boron–boron bonding lead to the formation of configurationally varied, vacancy-mediated structural motifs, providing unprecedented diversity in a mono-elemental 2D system with potential for electronic applications, chemical functionalization, materials synthesis and complex heterostructures. With its foundations in computationally guided synthesis, borophene can serve as a prototype for ongoing efforts to discover and exploit synthetic 2D materials.
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This work was performed, in part, at the Center for Nanoscale Materials, a US Department of Energy Office of Science User Facility, and supported by the US Department of Energy, Office of Science, under Contract no. DE-AC02-06CH11357. A.J.M. acknowledges the National Science Foundation Graduate Fellowship Program (DGE-1324585). The work at Rice University was supported by the Department of Energy (DE-SC0012547, structure–synthesis models) and in part by the Office of Naval Research (N00014-15-1-2372, electronics and superconductivity). Z.Z. acknowledges the support of NSFC (11772153). M.C.H. also acknowledges the Office of Naval Research (N00014-17-1-2993).
The authors declare no competing interests.
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Mannix, A.J., Zhang, Z., Guisinger, N.P. et al. Borophene as a prototype for synthetic 2D materials development. Nature Nanotech 13, 444–450 (2018). https://doi.org/10.1038/s41565-018-0157-4
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