Controlled growth of two-dimensional Sb₂Te₃ nanoflakes by chemical vapor deposition method

Two-dimensional Sb₂Te₃ with excellent thermoelectric and optoelectronic properties, has attracted significant interest for next-generation electronic and quantum devices. However, achieving controllable growth of high-quality, single-crystalline Sb₂Te₃ nanoflakes remains a major challenge. We report the successful growth of large-area, high-crystallinity Sb₂Te₃ nanoflakes on mica substrates via a dual-zone chemical vapor deposition (CVD) method using SbCl₃ and Te precursors. The effects of substrate type, growth duration, carrier gas, and gas flow rate on the growth behavior of Sb₂Te₃ nanoflakes were systematically investigated. Comprehensive structural and morphological characterizations, including Raman spectroscopy, SEM, and AFM, reveal that the Sb₂Te₃ nanoflakes grown on mica exhibit high crystallinity, uniform thickness, sharp edges, and superior orientation compared with those grown on sapphire and SiO₂/Si substrates. Furthermore, power-dependent Raman analysis indicates that irradiation of CVD-grown Sb₂Te₃, Sb, and Te with a 488 nm laser at powers of 1.0–4.0 mW results in the transformation of Sb₂Te₃ into Sb₂O₃, while elemental Sb and Te remain structurally stable under the same experimental conditions. This study demonstrates a scalable CVD approach for synthesizing Sb₂Te₃ nanoflakes and provides important insights into their growth mechanisms, stability, and potential use in future device applications.