Rakshit Subrata, Gonzalez Szwacki Nevill
Faculty of Physics, University of Warsaw, Pasteura 5, 02093, Warsaw, Poland.
Sci Rep. 2025 Jan 2;15(1):349. doi: 10.1038/s41598-024-82972-w.
Recent experimental realizations of bilayer boron materials motivated us to study the structure and properties of α-sheet-based bilayer borophenes with interlayer covalent bonds. As shown here, at least three stacking variations are possible: AA, AB, and [Formula: see text]. The on-top AA-stacking has been obtained experimentally supported on a metallic substrate. The AB-stacking is the most stable among neutral freestanding structures, whereas the AA and [Formula: see text] stacking sequences are very close in energy, both for neutral and negatively charged cases. The studied bilayer borophenes exhibit extraordinarily high electric conductivity with values as high as [Formula: see text] for the experimentally observed AA-stacking. The highly stable AB-stacking bilayer, reported here for the first time, exhibits an anisotropic conductivity with an average value of [Formula: see text]. Contrary to the AA-stacking bilayer that retains the 6-fold fold rotational symmetry of the α-sheet, the AB-stacking structure has 2-fold symmetry, which leads to the anisotropic transport properties.
最近双层硼材料的实验实现促使我们研究具有层间共价键的基于α-片层的双层硼烯的结构和性质。如下所示，至少有三种堆叠变体是可能的：AA、AB和[公式：见正文]。在金属衬底上已通过实验获得了顶部AA堆叠。在中性独立结构中，AB堆叠是最稳定的，而对于中性和带负电的情况，AA和[公式：见正文]堆叠序列在能量上非常接近。所研究的双层硼烯表现出极高的电导率，对于实验观察到的AA堆叠，其值高达[公式：见正文]。本文首次报道的高度稳定的AB堆叠双层表现出各向异性电导率，平均值为[公式：见正文]。与保留α-片层6重旋转对称性的AA堆叠双层相反，AB堆叠结构具有2重对称性，这导致了各向异性传输特性。
