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 Bi ₂Te₃ sheets grow in the basal plane of the hexagonal structure and are typically 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 Bi nanosheets.