Van der Waals Template‐Assisted Low‐Temperature Epitaxial Growth of 2D Atomic Crystals

Abstract To date, the synthesis of high‐quality 2D crystals using vapor deposition methods usually requires high temperature, hindering the integration of 2D materials with Si circuits and exacerbating energy consumption. Exploring low‐temperature growth strategies and understanding synthesis mechanism are critical for the practical application of 2D materials. Herein, a van der Waals (vdW) template‐assisted growth of 2D crystals (including PbI 2 , CdI 2 , BiI 3 , CuI, Sb 2 Te 3, and Bi 2 Se 3 ) is reported, the growth temperature decreases by maximum 35% compared with traditional vapor deposition. The low‐temperature 2D growth process resulting from the low surface diffusion barrier of precursors on vdW surfaces is proposed, confirmed by the density functional theory and molecular dynamics calculations. Particularly, the grown 2D crystals can be peeled off from vdW templates easily and transferred to arbitrary substrates for functional applications and the exfoliated vdW templates can be reused for another round of growth. Although the growth temperature is reduced greatly, the excellent photoelectric performance of grown 2D crystals is demonstrated, benefitting from high crystalline quality. These findings provide a universal method for the low‐temperature synthesis of high‐crystallinity 2D materials toward applications in flexible electronics.