Tri-wing bismuth telluride nanoribbons with quasi-periodic rough surfaces

Unique bismuth telluride nanostructures, tri-wing nanoribbons, are controllably synthesized on a large scale by a facile one-pot hydrothermal method. The length of the nanoribbon is up to tens of micrometres, and the wing of the nanoribbon is very thin with an average thickness of about 20 nm. During the synthesis process, tri-wing Te nanoribbons are first formed and act as the template, highly crystalline tri-wing Bi₂Te₃ nanoribbons are then obtained through a surface-directing diffusion process. An elaborate TEM study reveals a quasi-periodic rough surface with sequential (115) and (105) planes along the Bi₂Te₃ nanoribbon, which is ascribed to the coherent growth of Bi₂Te₃ crystals during the surface-directing diffusion process. The successful synthesis of Bi ₂Te₃ nanoribbons with rough surfaces opens up the opportunities of developing high performance nanoscale thermoelectrics as well as studying the surface state of Bi₂Te₃ nanoribbons as potential topological insulators.