Multilayer A17 Black Antimonene via van der Waals Epitaxy

Metastable layered antimony in the black phosphorus-like A17 phase exhibits promising electronic properties arising from pronounced spin-orbit coupling and suppressed phonon scattering. However, charge transport characterization has been severely constrained by insufficient crystal dimensions. Here, the dielectric-mediated van der Waals epitaxy of multilayer A17 black antimonene is reported, with the as-grown rectangular nanosheets exceeding 10 μm in length and exhibiting layer-dependent phase stability up to 16-layer stacking. Structural analysis reveals that monolayer nucleation favors zigzag and diagonal edge formation and shows that the multilayer structure adopts an AB-stacking configuration. Angle-dependent Raman vibration signatures are resolved, and the spectral benchmark is validated for identifying the zigzag crystal orientation. Structural stability in air over 3 weeks is confirmed through Raman modes. In the zigzag direction, the p-type carrier mobilities of 170 cm²·V^-1·s^-1 at room temperature and 287 cm²·V^-1·s^-1 at 10 K are corroborated using back-gate field-effect devices. With decent carrier mobilities in multilayer A17 black antimonene, this work offers an experimental platform for investigating exotic electronic properties in monolayer and few-layer A17 black antimonene.