Scalable synthesis of two-dimensional antimony telluride nanoplates down to a single quintuple layer

Abstract

Scalable syntheses of two-dimensional topological insulators are critical to material exploration. We demonstrate a controlled assembly of a two-dimensional V–VI group compound, Sb₂Te₃ nanoplates (NPs), through a vapor–solid growth process. The physical thickness of Sb₂Te₃ NPs can be rationally controlled in a wide range, from hundreds of nm down to sub-10 nm. Single-quintuple-layer Sb₂Te₃ NPs were obtained, with a high domain density of ∼2.465 × 10⁸ cm⁻² over a large surface area (1 cm × 1 cm) of a SiO₂/Si substrate, verifying a scalable synthesis method. Extensive material analyses were conducted to explore the basic properties of Sb₂Te₃ NPs using SEM and AFM, etc. HRTEM analysis confirms that the NP samples exhibit a highly crystalline structure and XPS analysis confirms the chemical composition and material stoichiometry. The growth of 2D topological insulator nanostructures may open up new opportunities in surface-state studies and potential applications in low-dissipative electronic systems.