Kinetics-Driven One-Dimensional Growth of van der Waals Layered SnSe

The one-dimensional (1D) form of van der Waals (vdW) layered compounds attracts growing interest due to their unusual physical properties and potential for nanoelectronic devices. However, the natural domain structure of vdW layered compounds is generally in a 2D form (nanosheets). Here, we report the high-quality 1D growth of vdW layered SnSe nanoribbons (NRs) via vapor deposition. The morphology evolution of SnSe products was systematically investigated. Angle-resolved polarized Raman spectroscopy and transmission electron microscopy analyses showed that the SnSe NRs are oriented along the [010] (zigzag, ZZ) direction. The intact morphology and good crystallinity suggest that the growth of SnSe NRs obeys a catalysis-free vapor-solid mechanism. Density functional theory calculations unveiled that the minimal migration barrier (0.33 eV) along the ZZ direction and the ZZ-oriented in-plane quasi-1D nature of SnSe are the main driving force of the 1D growth of vdW layered SnSe.