Van der Waals Heteroepitaxial Growth of Monolayer Sb in a Puckered Honeycomb Structure

Atomically thin 2D crystals have gained tremendous attention owing to their potential impact on future electronics technologies, as well as the exotic phenomena emerging in these materials. Monolayers of alpha-phase Sb (alpha-antimonene), which shares the same puckered structure as black phosphorous, are predicted to be stable with precious properties. However, the experimental realization still remains challenging. Here, high-quality monolayer alpha-antimonene is successfully grown, with the thickness finely controlled. The alpha-antimonene exhibits great stability upon exposure to air. Combining scanning tunneling microscopy, density functional theory calculations, and transport measurements, it is found that the electron band crossing the Fermi level exhibits a linear dispersion with a fairly small effective mass, and thus a good electrical conductivity. All of these properties make the alpha-antimonene promising for future electronic applications.