One‐Step Synthesis of Bismuth Telluride Nanosheets of a Few Quintuple Layers in Thickness

Bi2Te3 nanosheets have been synthesized on Si substrates by surface-assisted chemical vapor transport. The crumpled Bi2Te3 sheets grow in the basal plane of the hexagonal structure and are typically ≤3 nm in thickness (see picture; Te purple, Bi green). Raman studies found that modes involving atom displacement along the c axis that are inactive in the bulk material become Raman-active in the Bi2Te3 nanosheets.