From 2D AgTe Monolayer to 1D AgTe Nanowires: Tellurium Concentration Modulated Structural and Electronic Properties Transformation.

Controllably modulating the structure of transition-metal chalcogenides (TMCs) from 2D to 1D and tuning their electronic properties has drawn particular attention currently due to their remarkable properties and potential applications. In this work, by precisely controlling the chemical concentration of Te atoms, the transformation from the 2D honeycomb AgTe monolayer to high-quality and well-defined 1D AgTe nanowires on the Ag(111) substrate has been successfully achieved. The combination of scanning tunneling microscopy measurements and first-principles calculations has confirmed that the mechanism underlying the entire dimensional transformation lies in the directional movement of Ag atoms in the 2D AgTe monolayer regulated by the concentration of Te atoms. The scanning tunneling spectroscopy results reveal that the bandgap of as-synthesized 1D AgTe nanowires is 0.9 eV. Additionally, between the 2D honeycomb AgTe monolayer and the 1D AgTe nanowires, a 1D well-defined and sharp interface has emerged, with a 1D interface state existing at this interface due to charge accumulation. This work may provide valuable guidance for the preparation of 1D nanowires within TMCs, the exploration of novel physical properties, as well as the development of future quantum devices.