Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan 44919, Republic of Korea.
Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea.
Nano Lett. 2021 Jul 28;21(14):6336-6342. doi: 10.1021/acs.nanolett.1c00915. Epub 2021 May 5.
Intercalation in black phosphorus (BP) can induce and modulate a variety of the properties including superconductivity like other two-dimensional (2D) materials. In this perspective, spatially controlled intercalation has the possibility to incorporate different properties into a single crystal of BP. We demonstrate anisotropic angstrom-wide (∼4.3 Å) Cu intercalation in BP, where Cu atoms are intercalated along a zigzag direction of BP because of its inherent anisotropy. With atomic structure, its microstructural effects, arising from the angstrom-wide Cu intercalation, were investigated and extended to relation with macrostructure. As the intercalation mechanism, it was revealed by in situ transmission electron microscopy and theoretical calculation that Cu atoms are intercalated through top-down direction of BP. The Cu intercalation anisotropically induces transition of angstrom-wide electronic channels from semiconductor to semimetal in BP. Our findings throw light on the fundamental relationship between microstructure changes and properties in intercalated BP, and tailoring anisotropic 2D materials at angstrom scale.
层间插入黑磷（BP）可以诱导和调节多种性质，包括像其他二维（2D）材料一样的超导性。在这种观点下，空间控制的层间插入有可能将不同的性质纳入到 BP 的单个晶体中。我们证明了 BP 中各向异性的埃（Å）级（约 4.3 Å）Cu 层间插入，由于其固有各向异性，Cu 原子沿着 BP 的锯齿形方向插入。通过原子结构、微观结构效应，以及与宏观结构的关系，研究了由于 Å 级 Cu 层间插入而产生的微观结构效应。作为层间插入机制，通过原位透射电子显微镜和理论计算揭示了 Cu 原子通过 BP 的自上而下方向插入。Cu 层间插入各向异性地诱导 BP 中埃级电子通道从半导体到半金属的转变。我们的发现阐明了层间 BP 中微观结构变化和性质之间的基本关系，并在 Å 级尺度上定制各向异性的 2D 材料。
