Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute , Troy, New York 12180, United States.
Nano Lett. 2014 Nov 12;14(11):6400-6. doi: 10.1021/nl502892t. Epub 2014 Oct 30.
Single-layer black phosphorus (BP), or phosphorene, is a highly anisotropic two-dimensional elemental material possessing promising semiconductor properties for flexible electronics. However, the direct bandgap of single-layer black phosphorus predicted theoretically has not been directly measured, and the properties of its edges have not been considered in detail. Here we report atomic scale electronic variation related to strain-induced anisotropic deformation of the puckered honeycomb structure of freshly cleaved black phosphorus using a high-resolution scanning tunneling spectroscopy (STS) survey along the light (x) and heavy (y) effective mass directions. Through a combination of STS measurements and first-principles calculations, a model for edge reconstruction is also determined. The reconstruction is shown to self-passivate most dangling bonds by switching the coordination number of phosphorus from 3 to 5 or 3 to 4.
单层黑磷（BP），又称磷烯，是一种各向异性的二维元素材料，具有用于柔性电子学的有前途的半导体特性。然而，理论上预测的单层黑磷的直接带隙尚未被直接测量，并且其边缘的性质也没有被详细考虑。在这里，我们使用高分辨率扫描隧道光谱（STS）沿轻（x）和重（y）有效质量方向对新剥离的黑磷的褶皱蜂窝结构的应变诱导各向异性变形相关的原子尺度电子变化进行了报道。通过结合 STS 测量和第一性原理计算，还确定了边缘重构的模型。结果表明，重构通过将磷的配位数从 3 变为 5 或 3 变为 4，从而自钝化大多数悬空键。
