Yang Xiaowei, Zhou Si, Huang Shiliang, Zhao Jijun
Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Ministry of Education, Dalian 116024, China.
Research Center of Energetic Material Genome Science, Institute of Chemical Materials, China Academy of Engineering Physics (CAEP), Mianyang 621900, China.
J Chem Phys. 2021 Apr 7;154(13):134702. doi: 10.1063/5.0044210.
Pressure-induced phase transition of boron nitride nanotubes (BNNTs) provides an effective approach to develop new boron nitride nanostructures with more desirable functions than those of carbon nanotubes, owing to the unique polar B-N bonds. However, the synthetic BNNTs usually comprise double- or multi-walls, whose structural evolution under pressure is complicated and remains largely elusive. Here, we unveil the complete phase transition behavior of hexagonal bundles of double-walled (DW) BNNTs of different chirality and diameters under hydrostatic pressures of up to 60 GPa. A series of new monolith phases are obtained from the compressed DW-BNNT bundles, whose structures can be well retained even after releasing the pressure. The bonding characters; electronic, optical, and mechanical properties; and Raman signature of these monolith phases are elucidated, which provide essential guidance for synthesis of new boron nitride materials with unprecedented properties for technological applications.
由于独特的极性B-N键，氮化硼纳米管（BNNTs）的压力诱导相变提供了一种有效的方法来开发具有比碳纳米管更理想功能的新型氮化硼纳米结构。然而，合成的BNNTs通常由双层或多层组成，其在压力下的结构演变复杂，在很大程度上仍然难以捉摸。在此，我们揭示了不同手性和直径的双层（DW）BNNTs的六角形束在高达60 GPa的静水压力下的完整相变行为。从压缩的DW-BNNT束中获得了一系列新的整体相，即使在释放压力后其结构仍能很好地保留。阐明了这些整体相的键合特征、电子、光学和机械性能以及拉曼特征，这为合成具有前所未有的性能以用于技术应用的新型氮化硼材料提供了重要指导。
